BZOJ3170: [Tjoi2013]松鼠聚会(切比雪夫距离转曼哈顿距离)

#include<cstdio>
#include<algorithm>
#define LL long long 
using namespace std;
const int MAXN = 1e5 + 10;
const LL INF = 1e18 + 10;
inline int read() {
    char c = getchar();int x = 0,f = 1;
    while(c < '0' || c > '9'){if(c == '-')f = -1;c = getchar();}
    while(c >= '0' && c <= '9'){x = x * 10 + c - '0',c = getchar();}
    return x * f;
}
LL N, x[MAXN], y[MAXN], sortx[MAXN], sorty[MAXN], sumx[MAXN], sumy[MAXN];
LL QueryX(int l, int r) {
    return sumx[r] - sumx[l - 1];
}
LL QueryY(int l, int r) {
    return sumy[r] - sumy[l - 1];
}
LL calc(LL k) {
    LL posx = lower_bound(sortx + 1, sortx + N + 1, x[k]) - sortx,
        posy = lower_bound(sorty + 1, sorty + N + 1, y[k]) - sorty;
    return posx * sortx[posx] - QueryX(1, posx) - (N - posx) * sortx[posx] + QueryX(posx + 1, N) + 
           posy * sorty[posy] - QueryY(1, posy) - (N - posy) * sorty[posy] + QueryY(posy + 1, N);
}
int main() {
#ifdef WIN32
    freopen("a.in", "r", stdin);
#endif
    N = read();
    for(int i = 1; i <= N; i++) {
        int a = read(), b = read();
        x[i] = sortx[i] = a + b,
        y[i] = sorty[i] = a - b;        
    }
    sort(sortx + 1, sortx + N + 1);
    sort(sorty + 1, sorty + N + 1);
    for(int i = 1; i <= N; i++) 
        sumx[i] = sumx[i - 1] + sortx[i],
        sumy[i] = sumy[i - 1] + sorty[i];
    LL ans = INF;
    for(int i = 1; i <= N; i++)
        ans = min(ans, calc(i));
    printf("%lld", ans >> 1);
    return 0;
}