-
Notifications
You must be signed in to change notification settings - Fork 0
/
MergeIntervals.cpp
64 lines (55 loc) · 1.54 KB
/
MergeIntervals.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
// Merge Intervals
/***
Given an array of intervals where intervals[i] = [starti, endi],
merge all overlapping intervals,
and return an array of the non-overlapping intervals
that cover all the intervals in the input.
Input: intervals = [[1,3],[2,6],[8,10],[15,18]]
Output: [[1,6],[8,10],[15,18]]
Explanation: Since Intervals [1,3] and [2,6] overlaps, merge them into [1,6].
Input: intervals = [[1,4],[4,5]]
Output: [[1,5]]
Explanation: Intervals [1,4] and [4,5] are considered overlapping.
***/
#include <iostream>
#include <algorithm>
#include <stack>
#define SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
using namespace std;
struct interval {
int start;
int end;
};
bool compareInterval(interval i1, interval i2) {
return (i1.start < i2.start);
}
void mergeOverlappingIntervals(interval *arr, int n) {
if (n <= 0) {
return;
}
stack<interval> s;
sort(arr, arr + n, compareInterval);
s.push(arr[0]);
for (int i = 1; i < n; ++i) {
interval top = s.top();
if (top.end < arr[i].start) {
s.push(arr[i]);
} else if (top.end < arr[i].end) {
top.end = arr[i].end;
s.pop();
s.push(top);
}
}
cout << "Merged intervals: " << endl;
while (!s.empty()) {
interval i = s.top();
cout << "{" << i.start << ", " << i.end << "}" << " ";
s.pop();
}
cout << endl;
}
int main() {
interval arr[] = {{12, 14}, {11, 13}, {20, 22}, {21, 23}};
mergeOverlappingIntervals(arr, SIZE(arr));
return 0;
}