题目链接：耍杂技的牛

#include <iostream>
#include <algorithm>using namespace std;typedef pair<int, int> PII;const int N = 50010;int n;
PII cow[N];int main()
{cin >> n;for(int i = 0; i < n; i ++){int w, s;cin >> w >> s;cow[i] = {w + s, w};}sort(cow, cow + n);// sum: 每头牛上面的重量之和int res = -2e9, sum = 0;for(int i = 0; i < n; i ++){int w = cow[i].second, s = cow[i].first - w;res = max(res, sum - s);sum += w;}cout << res << endl;return 0;
}