hdu 5124 lines（贪心）

题目链接：hdu 5124 lines

#include <cstdio>#include <cstring>#include <vector>#include <algorithm>using namespace std;typedef pair<int,int> pii;int N;vector<pii> vec;int main () {int cas, x, y;scanf("%d", &cas);while (cas--) {scanf("%d", &N);vec.clear();for (int i = 0; i < N; i++) {scanf("%d%d", &x, &y);vec.push_back(make_pair(x, 1));vec.push_back(make_pair(y + 1, -1));}sort(vec.begin(), vec.end());int ans = 0, p = 0;for (int i = 0; i < vec.size(); i++) {p += vec[i].second;ans = max(ans, p);}printf("%d\n", ans);}return 0;}