UVA 11729 Commando War

#include<cstdio>
#include<algorithm>
#include<iostream>
#include<cstring>
using namespace std;
struct node{int x,y;}man[1005];
int last[1005];
bool cmp(const node &a,const node &b)
{
    return a.y>b.y;
}
int main()
{
    int n;
    int cas=1;
    while(scanf("%d",&n)&&n)
    {
        int ans=0;
        int sum=0;
        last
=0;
        for(int i=1;i<=n;i++)
        {
            scanf("%d%d",&man[i].x,&man[i].y);
            sum+=man[i].x;
        }
        sort(man+1,man+1+n,cmp);
        for(int i=n-1;i>=1;i--)
        {
            last[i]=last[i+1]+man[i+1].x;
        }
        for(int i=1;i<=n;i++)
        {
            if(man[i].y>last[i]) ans=max(ans,man[i].y-last[i]);
        }
        printf("Case %d: %d\n",cas++,ans+sum);
    }
    return 0;
}