[P2119]魔法阵 (模拟？搜索？)

很玄学

我暴力都没做出来

#include <cstdio>
int n,m,x[],vis[],a[],b[],c[],d[];
int main() {
    //freopen("magic.in","r",stdin);
    //freopen("magic.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (int i = ;i <= m;i++) {
        scanf("%d",&x[i]);
        vis[x[i]]++;
    }
    for (int i = ;i <= n/;i++) {
        int sum = ;
        for (int j = i*+;j <= n;j++) {
            sum += vis[j-(*i+)]*vis[j-(*i+)+*i];
            d[j] += sum*vis[j-i];
            c[j-i]+=sum*vis[j];
        }
        sum = ;
        for (int j = n-(*i+);j >= ;j--) {
            sum += vis[j+(*i+)]*vis[j+(*i+)-i];
            a[j] += sum*vis[j+*i];
            b[j+*i] += sum*vis[j];

        }
    }
    for (int i = ;i <= m;i++) printf("%d %d %d %d\n",a[x[i]],b[x[i]],c[x[i]],d[x[i]]);
    return ;
}