蒟蒻求助

#include<bits/stdc++.h>
#define ll long long
#define N 20005
using namespace std;
int T,n;
ll sum[N],cnt=0;
struct node{
    int a,b,d;
    bool operator <(node x) const
    {
        if (d!=x.d) return d<x.d;
        if (d<=0) return a<x.a;
        return b>x.b;
    }
}s[N];
int main(){
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        for(int i=1;i<=n;i++){
            scanf("%d%d",&s[i].a,&s[i].b);
            if(s[i].a<s[i].b) s[i].d=-1;
            else if(s[i].a>s[i].b) s[i].d=1;
            else s[i].d=0;
        }
        sort(s+1,s+n+1);
        cnt=0;
        for(int i=1;i<=n;i++){
            cnt+=s[i].a;
            sum[i]=max(sum[i-1],cnt)+s[i].b;
        }
        printf("%lld\n",sum[n]);
    }
}

#include<bits/stdc++.h>
#define ll long long
#define N 20005
using namespace std;
int T,n;
ll sum[N],cnt=0;
struct node{
    int a,b,d;
}s[N];
bool cmp(node x,node y){
    if(x.d!=y.d) return x.d<y.d;
    if(x.d>=0) return x.a<y.a;
    return x.b>y.b;
}
int main(){
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        for(int i=1;i<=n;i++){
            scanf("%d%d",&s[i].a,&s[i].b);
            if(s[i].a<s[i].b) s[i].d=-1;
            else if(s[i].a>s[i].b) s[i].d=1;
            else s[i].d=0;
        }
        sort(s+1,s+n+1,cmp);
        cnt=0;
        for(int i=1;i<=n;i++){
            cnt+=s[i].a;
            sum[i]=max(sum[i-1],cnt)+s[i].b;
        }
        printf("%lld\n",sum[n]);
    }
}