Merge pull request #45 from himanshusanecha/master

Created merge-intervals.cpp file

Merge-intervals.cpp

@@ -0,0 +1,59 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+vector < vector < int >> merge(vector < vector < int >> & intervals) {
+  vector < vector < int >> ans;
+  vector < pair < int, int > > s;
+  stack < pair < int, int >> stack;
+
+  for (int i = 0; i < intervals.size(); i++) {
+    s.push_back(make_pair(intervals[i][0], intervals[i][1]));
+  }
+
+  sort(s.begin(), s.end());
+  stack.push(s[0]);
+  for (int i = 0; i < intervals.size(); i++) {
+    auto it = stack.top();
+    if (it.second >= s[i].first) {
+      stack.pop();
+      if (it.second < s[i].second)
+        stack.push(make_pair(it.first, s[i].second));
+      else
+        stack.push(make_pair(it.first, it.second));
+    } else
+      stack.push(make_pair(s[i].first, s[i].second));
+  }
+  while (stack.empty() != true) {
+    auto it = stack.top();
+    ans.push_back({
+      it.first,
+      it.second
+    });
+    stack.pop();
+  }
+  return ans;
+}
+int main() {
+  vector < vector < int >> v;
+  v.push_back({
+    6,
+    8
+  });
+  v.push_back({
+    1,
+    9
+  });
+  v.push_back({
+    2,
+    4
+  });
+  v.push_back({
+    4,
+    7
+  });
+  v = merge(v);
+  for (int i = 0; i < v.size(); i++) {
+    cout << v[i][0] << " " << v[i][1] << endl;
+  }
+}