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feat: add solutions to lc problem: No.0367
No.0367.Valid Perfect Square
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‎solution/0000-0099/0052.N-Queens II/README.md‎

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@@ -15,7 +15,7 @@
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<div class="original__bRMd">
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<div>
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<p><strong>示例 1：</strong></p>
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<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/queens.jpg" style="width: 600px; height: 268px;" />
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<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/8-queens.png" style="width: 600px; height: 268px;" />
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<pre>
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<strong>输入：</strong>n = 4
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<strong>输出：</strong>2

‎solution/0000-0099/0052.N-Queens II/README_EN.md‎

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<p>&nbsp;</p>
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<p><strong>Example 1:</strong></p>
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<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/queens.jpg" style="width: 600px; height: 268px;" />
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<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/8-queens.png" style="width: 600px; height: 268px;" />
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<pre>
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<strong>Input:</strong> n = 4
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<strong>Output:</strong> 2

‎solution/0300-0399/0367.Valid Perfect Square/README.md‎

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@@ -38,7 +38,11 @@
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<!-- 这里可写通用的实现逻辑 -->
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二分法。
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**1. 二分查找**
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**2. 转换为数学问题**
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由于 `n² = 1 + 3 + 5 + ... + (2n-1)`，对数字 num 不断减去 i (`i = 1, 3, 5, ...`) 直至 num 不大于 0，如果最终 num 等于 0，说明是一个有效的完全平方数。
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<!-- tabs:start -->
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@@ -51,25 +55,35 @@ class Solution:
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def isPerfectSquare(self, num: int) -> bool:
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left, right = 1, num
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while left < right:
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mid = left + ((right - left) >> 1)
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if num // mid <= mid:
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mid = (left + right) >> 1
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if mid * mid >= num:
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right = mid
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else:
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left = mid + 1
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return left * left == num
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```
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```python
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class Solution:
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def isPerfectSquare(self, num: int) -> bool:
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i = 1
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while num > 0:
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num -= i
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i += 2
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return num == 0
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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public boolean isPerfectSquare(int num) {
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int left = 1, right = num;
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long left = 1, right = num;
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while (left < right) {
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int mid = (left + right) >>> 1;
72-
if (num / mid <= mid) {
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long mid = (left + right) >>> 1;
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if (mid * mid >= num) {
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right = mid;
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} else {
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left = mid + 1;
@@ -80,34 +94,53 @@ class Solution {
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}
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```
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```java
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class Solution {
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public boolean isPerfectSquare(int num) {
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for (int i = 1; num > 0; i += 2) {
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num -= i;
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}
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return num == 0;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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bool isPerfectSquare(int num) {
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long left = 1, right = num;
90-
while (left < right) {
91-
int mid = left + ((right - left) >> 1);
92-
if (num / mid <= mid) {
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right = mid;
94-
} else {
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left = mid + 1;
96-
}
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while (left < right)
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{
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long mid = left + right >> 1;
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if (mid * mid >= num) right = mid;
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else left = mid + 1;
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}
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return left * left == num;
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}
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};
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```
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```cpp
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class Solution {
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public:
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bool isPerfectSquare(int num) {
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for (int i = 1; num > 0; i += 2) num -= i;
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return num == 0;
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}
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};
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```
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### **Go**
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```go
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func isPerfectSquare(num int) bool {
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left, right := 1, num
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for left < right {
109-
mid := left + (right-left)>>1
110-
if num/mid <= mid {
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mid := (left + right) >> 1
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if mid*mid >= num {
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right = mid
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} else {
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left = mid + 1
@@ -117,6 +150,15 @@ func isPerfectSquare(num int) bool {
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}
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```
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```go
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func isPerfectSquare(num int) bool {
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for i := 1; num > 0; i += 2 {
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num -= i
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}
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return num == 0
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}
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```
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### **...**
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```

‎solution/0300-0399/0367.Valid Perfect Square/README_EN.md‎

Lines changed: 52 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -34,23 +34,33 @@ class Solution:
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def isPerfectSquare(self, num: int) -> bool:
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left, right = 1, num
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while left < right:
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mid = left + ((right - left) >> 1)
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if num // mid <= mid:
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mid = (left + right) >> 1
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if mid * mid >= num:
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right = mid
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else:
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left = mid + 1
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return left * left == num
4343
```
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```python
46+
class Solution:
47+
def isPerfectSquare(self, num: int) -> bool:
48+
i = 1
49+
while num > 0:
50+
num -= i
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i += 2
52+
return num == 0
53+
```
54+
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### **Java**
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4757
```java
4858
class Solution {
4959
public boolean isPerfectSquare(int num) {
50-
int left = 1, right = num;
60+
long left = 1, right = num;
5161
while (left < right) {
52-
int mid = (left + right) >>> 1;
53-
if (num / mid <= mid) {
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long mid = (left + right) >>> 1;
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if (mid * mid >= num) {
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right = mid;
5565
} else {
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left = mid + 1;
@@ -61,34 +71,53 @@ class Solution {
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}
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```
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```java
75+
class Solution {
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public boolean isPerfectSquare(int num) {
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for (int i = 1; num > 0; i += 2) {
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num -= i;
79+
}
80+
return num == 0;
81+
}
82+
}
83+
```
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### **C++**
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6687
```cpp
6788
class Solution {
6889
public:
6990
bool isPerfectSquare(int num) {
7091
long left = 1, right = num;
71-
while (left < right) {
72-
int mid = left + ((right - left) >> 1);
73-
if (num / mid <= mid) {
74-
right = mid;
75-
} else {
76-
left = mid + 1;
77-
}
92+
while (left < right)
93+
{
94+
long mid = left + right >> 1;
95+
if (mid * mid >= num) right = mid;
96+
else left = mid + 1;
7897
}
7998
return left * left == num;
8099
}
81100
};
82101
```
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103+
```cpp
104+
class Solution {
105+
public:
106+
bool isPerfectSquare(int num) {
107+
for (int i = 1; num > 0; i += 2) num -= i;
108+
return num == 0;
109+
}
110+
};
111+
```
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### **Go**
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86115
```go
87116
func isPerfectSquare(num int) bool {
88117
left, right := 1, num
89118
for left < right {
90-
mid := left + (right-left)>>1
91-
if num/mid <= mid {
119+
mid := (left + right) >> 1
120+
if mid*mid >= num {
92121
right = mid
93122
} else {
94123
left = mid + 1
@@ -98,6 +127,15 @@ func isPerfectSquare(num int) bool {
98127
}
99128
```
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130+
```go
131+
func isPerfectSquare(num int) bool {
132+
for i := 1; num > 0; i += 2 {
133+
num -= i
134+
}
135+
return num == 0
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}
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```
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101139
### **...**
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103141
```

‎solution/0300-0399/0367.Valid Perfect Square/Solution.cpp‎

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Original file line numberDiff line numberDiff line change
@@ -2,13 +2,11 @@ class Solution {
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public:
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bool isPerfectSquare(int num) {
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long left = 1, right = num;
5-
while (left < right) {
6-
int mid = left + ((right - left) >> 1);
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if (num / mid <= mid) {
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right = mid;
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} else {
10-
left = mid + 1;
11-
}
5+
while (left < right)
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{
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long mid = left + right >> 1;
8+
if (mid * mid >= num) right = mid;
9+
else left = mid + 1;
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}
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return left * left == num;
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}

‎solution/0300-0399/0367.Valid Perfect Square/Solution.go‎

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Original file line numberDiff line numberDiff line change
@@ -1,8 +1,8 @@
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func isPerfectSquare(num int) bool {
22
left, right := 1, num
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for left < right {
4-
mid := left + (right-left)>>1
5-
if num/mid <= mid {
4+
mid := (left + right) >> 1
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if mid*mid >= num {
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right = mid
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} else {
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left = mid + 1

‎solution/0300-0399/0367.Valid Perfect Square/Solution.java‎

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Original file line numberDiff line numberDiff line change
@@ -1,9 +1,9 @@
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class Solution {
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public boolean isPerfectSquare(int num) {
3-
int left = 1, right = num;
3+
long left = 1, right = num;
44
while (left < right) {
5-
int mid = (left + right) >>> 1;
6-
if (num / mid <= mid) {
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long mid = (left + right) >>> 1;
6+
if (mid * mid >= num) {
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right = mid;
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} else {
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left = mid + 1;

‎solution/0300-0399/0367.Valid Perfect Square/Solution.py‎

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Original file line numberDiff line numberDiff line change
@@ -2,8 +2,8 @@ class Solution:
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def isPerfectSquare(self, num: int) -> bool:
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left, right = 1, num
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while left < right:
5-
mid = left + ((right - left) >> 1)
6-
if num // mid <= mid:
5+
mid = (left + right) >> 1
6+
if mid * mid >= num:
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right = mid
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else:
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left = mid + 1

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