题目链接

题面:

题解:

代码:

#include<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
#include<algorithm>
#define int long long
using namespace std;
const int inf=0x3f3f3f3f;
const int maxn=20100;
struct node
{
    int a,b,d;
    bool operator <(const node &pm) const
    {
        if(d!=pm.d) return d<pm.d;
        if(d<=0) return a<pm.a;
        else return b>pm.b;
    }
}a[maxn];
int c[maxn];

signed main(void)
{
    int t;
    scanf("%lld",&t);
    while(t--)
    {
        int n;
        scanf("%lld",&n);
        for(int i=1;i<=n;i++)
        {
            scanf("%lld%lld",&a[i].a,&a[i].b);
            if(a[i].a<a[i].b) a[i].d=-1;
            else if(a[i].a>a[i].b) a[i].d=1;
            else a[i].d=0;
        }
        sort(a+1,a+n+1);
        int sum=0;
        for(int i=1;i<=n;i++)
        {
            sum+=a[i].a;
            c[i]=max(c[i-1],sum)+a[i].b;
        }
        printf("%lld\n",c[n]);
    }
    return 0;
}