2017 多校训练第二场 HDU 6052 To my boyfriend

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn=105;
int num[maxn][maxn];
int n,m;

ll cal(int x, int y) {
    ll res=0;
    int c=num[x][y],L=1,R=m;
    for (int i=x;i>=1;i--) {
        if(i<x&&num[i][y]==c) break;
        int l=y,r=y;
        for(int j=y-1;j>=max(1,L);j--) {
            if(num[i][j]==c) break;
            l=j;
        }
        L=max(L,l);
        if(i==x){
            res+=(ll)(n-x+1LL)*(y-L+1LL)*(R-y+1LL);
            continue;
        }
        for(int j=y+1;j<=min(m,R);j++) {
            if(num[i][j]==c) break;
            r=j;
        }
        R=min(R,r);
        res+=(ll)(n-x+1LL)*(y-L+1LL)*(R-y+1LL);
    }
    //printf("(%d, %d) %I64d\n", x, y, res);
    return res;
}

int main(int argc, char const *argv[])
{
	int T;
	scanf("%d",&T);
	while(T--){
		scanf("%d %d",&n,&m);
		ll cnt=0;
		for(int i=1;i<=n;i++){
			for(int j=1;j<=m;j++){
				cnt+=(i*j);
				scanf("%d",&num[i][j]);
			}
		}
		ll kkk=0;
		for(int i=1;i<=n;i++){
			for(int j=1;j<=m;j++){
				kkk+=cal(i,j);
			}
		}
		printf("%.9f\n",kkk*1.0/cnt);
	}
	return 0;
}#include <bits/stdc++.h>
using namespace std;
t