【HDU 4311】Meeting point-1（前缀和求曼哈顿距离和）

#include<cstdio>
#include<algorithm>
using namespace std;
#define ll long long
#define N 100005
int t,n;
ll ans,sum[N],sx[N],sy[N];
struct p
{
    int i;
    ll x,y;
} a[N];
int cmpx(p a,p b)
{
    return a.x<b.x;
}
int cmpy(p a,p b)
{
    return a.y<b.y;
}
int main()
{
    scanf("%d",&t);
    while(t--)
    {
        sx[0]=sy[0]=0;
        scanf("%d",&n);
        for(int i=1; i<=n; i++)
        {
            scanf("%lld%lld",&a[i].x,&a[i].y);
            a[i].i=i;
        }
        sort(a+1,a+n+1,cmpx);
        for(int i=1; i<=n; i++)
            sx[i]=sx[i-1]+a[i].x;
        for(int i=1;i<=n;i++)
            sum[a[i].i]=a[i].x*(i-1)-sx[i-1]+sx[n]-sx[i]-a[i].x*(n-i);
        sort(a+1,a+n+1,cmpy);
        for(int i=1; i<=n; i++)
            sy[i]=sy[i-1]+a[i].y;
        for(int i=1; i<=n; i++)
        {
            sum[a[i].i]+=a[i].y*(i-1)-sy[i-1]+sy[n]-sy[i]-a[i].y*(n-i);
            ans=(i==1)?sum[a[1].i]:min(ans,sum[a[i].i]);
        }
        printf("%lld\n",ans);
    }
}

#include<cstdio>
#include<algorithm>
using namespace std;
#define ll long long
struct p{ll x,y;}a[100005];
ll ABS(ll a){
    if(a<0)a=-a;
    return a;
}
ll dis(p a, p b){
    return ABS(a.x-b.x)+ABS(a.y-b.y);
}
int cmp(p a,p b){
    return a.x<b.x;
}
int main(){
    int t,n,s,e;
    scanf("%d",&t);
    while(t--){
        scanf("%d",&n);
        for(int i=1;i<=n;i++)
            scanf("%lld%lld",&a[i].x,&a[i].y);
        sort(a+1,a+1+n,cmp);
        s=n/2-223;
        e=n/2+223;
        if(s<1)s=1;
        if(e>n)e=n;
        ll ans=1LL<<60;
        for(int z=s;z<=e;z++){
            ll s=0;
            for(int i=1;i<=n;i++)
                s+=dis(a[z],a[i]);
            ans=min(s,ans);
        }
        printf("%lld\n",ans);
    }
}