与114.国王游戏 （https://www.acwing.com/problem/content/116/） 一样的思路，为了使风险值的最大值最小，应该将牛按照W+S从小到大的顺序从下往上排列。

C++ 代码

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

vector<int> sums;

bool cmp(int a, int b)
{
    return sums[a] < sums[b];
}

int main()
{
    int N, W, S;
    cin >> N;
    vector<int> Ws(N), Ss(N), ranks(N);
    sums.resize(N);
    for (int i = 0; i < N; i++) {
        cin >> W >> S;
        Ws[i] = W;
        Ss[i] = S;
        sums[i] = W + S;
        ranks[i] = i;
    }

    sort(ranks.begin(), ranks.end(), cmp);

    int result = -1000000000;
    int sum_W = 0;
    for (int i = 0; i < N; i++) {
        int cur_id = ranks[i];
        result = max(result, sum_W - Ss[cur_id]);
        sum_W += Ws[cur_id];
    }

    cout << result;

    return 0;
}