/
45.cpp
176 lines (168 loc) · 4.35 KB
/
45.cpp
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__________________________________________________________________________________________________
8ms
class Solution {
public:
int jump(vector<int>& nums) {
int cur_max_end = 0;
int next_max_end = 0;
int length = nums.size();
if (length < 2) return 0;
int count = 0;
for (int i = 0; i < length; ++i) {
// cout << "cur_max_end: " << cur_max_end << endl;
// cout << "next_max_end: " << next_max_end << endl;
if (cur_max_end == 0) {
cur_max_end = i + nums[i];
next_max_end = cur_max_end;
++count;
if (next_max_end >= length - 1) return count;
} else if (i <= cur_max_end) {
auto tmp = i + nums[i];
if (tmp > next_max_end) {
next_max_end = tmp;
} else {
continue;
}
} else {
++count;
cur_max_end = next_max_end;
next_max_end = max(next_max_end, i + nums[i]);
}
if (next_max_end >= length - 1) break;
}
return count + 1;
}
};
auto ___ = []() {
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
return 0;
}();
__________________________________________________________________________________________________
12ms
class Solution {
public:
int jump(vector<int>& nums) {
int pos = 0;
int jump = 0;
int jump_num = 0;
while (pos<nums.size()) {
int max_j = 0;
for (int i = 0; i <= nums[pos]; i++) {
if (pos + i == nums.size() - 1) {
if (i == 0) {
return jump;
}
return jump + 1;
}
if (i + nums[pos + i]>=max_j) {
max_j = i + nums[pos + i];
jump_num = i;
}
}
pos = pos + jump_num;
jump++;
}
return jump;
}
};
__________________________________________________________________________________________________
16ms
class Solution {
public:
int jump(vector<int>& nums) {
int n=nums.size();
if(n==0||n==1)
return 0;
int temp,p=0,step=0,right=0;
while(p<n)
{
step++;
temp=right;
for(int i=p;i<=temp;i++)
right=max(right,i+nums[i]);
if(right>=n-1)
return step;
p++;
}
return step;
}
};
__________________________________________________________________________________________________
9924 kb
static int speedup = [](){
std::ios::sync_with_stdio(0);
std::cin.tie(0);
return 0;
}();
class Solution {
public:
int jump(vector<int>& nums) {
int n = nums.size();
if(n == 0|| n == 1){
return 0;
}
for(int i = 0; i < n; i++){
if(nums[i] == 0){
nums[i] = 1;
}
}
int jump_count = 1;
int end = nums[0];
int t = end;
if(t >= n-1){
return jump_count;
}
// range initially is 0 to nums[0];
int k = 1;
while(k < n){
jump_count++;
while(k <= end){
t = max(t, k + nums[k]);
if(t >= n-1){
return jump_count;
}
k++;
}
if(k > t){
return -1;
}else{
end = t;
}
}
return -1;
}
};
__________________________________________________________________________________________________
10228 kb
static int speedup = [](){
std::ios::sync_with_stdio(0);
std::cin.tie(0);
return 0;
}();
class Solution {
public:
int jump(vector<int>& nums) {
int n = nums.size();
if(n == 0 || n == 1){
return 0;
}
for(int i = 0; i < n; i++){
if(nums[i] == 0){
nums[i] = 1;
}
}
vector<int> num_jumps(n,n-1);
num_jumps[0] = 0;
for(int i = 0; i < n; i++){
for(int j = 0; j < i; j++){
if(j + nums[j] >= i){
num_jumps[i] = min(num_jumps[i], num_jumps[j]+1);
}
}
}
return num_jumps[n-1];
}
};
__________________________________________________________________________________________________