125. 耍杂技的牛（贪心）

 　　分析：先按照w+s排序，从前到后遍历即可

#include <bits/stdc++.h>
using namespace std;

const int N = 50050;
typedef pair<int,int> PII;

PII f[N];
int n;
int main() {
    scanf("%d",&n);
    for(int i = 0; i < n; i++) {
        int w, s;
        scanf("%d%d",&w,&s);
        f[i] = {w+s,w};
    }
    sort(f,f+n);
    int res = -2e9, sum = 0;
    for(int i = 0; i < n; i++) {
        int t = f[i].first, w = f[i].second;
        res = max(res,sum-(t-w));
        sum += w;
    }
    printf("%d\n",res);
    return 0;
}