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35 lines
735 B
C++
35 lines
735 B
C++
#include<bits/stdc++.h>
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using namespace std;
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bool cmp(pair<int, int> a, pair<int, int> b) {
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return a.first == b.first ? a.second < b.second : a.first < b.first;
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}
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int main() {
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int n;
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pair<int, int> p[200005];
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cin >> n;
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for(int i = 0 ; i < n ; i++) {
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cin >> p[i].first >> p[i].second;
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}
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sort(p, p+n, cmp);
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int tv1 = -1, tv2 = -1;
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for(int i = 0 ; i < n ; i++) {
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if(p[i].first > tv1) {
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tv1 = p[i].second;
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}
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else {
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if(p[i].first > tv2) {
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tv2 = p[i].second;
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}
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else {
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cout << "NO" << endl;
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return 0;
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}
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}
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}
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cout << "YES" << endl;
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return 0;
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}
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