Gym 101102D---Rectangles(单调栈)

#include <iostream>
#include <algorithm>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <set>
#include <queue>
#include <vector>
using namespace std;
int a[1005][1005];
int h[1005][1005];
int ans[1005][1005];///包含某一点的贡献值;
int S[1005],pos[1005];///单调栈;

int main()
{
    int T;
    cin>>T;
    int R,C;
    while(T--)
    {
        scanf("%d%d",&R,&C);
        memset(h,0,sizeof(h));
        memset(a,0,sizeof(a));
        memset(ans,0,sizeof(ans));
        for(int i=1;i<=R;i++)
            for(int j=1;j<=C;j++)
            scanf("%d",&a[i][j]);
        for(int j=1;j<=C;j++)
        {
            int s;
            for(int i=1;i<=R;i++)
            {
                if(a[i][j]==a[i-1][j]) s++;
                else s=1;
                h[i][j]=s;
            }
        }
        long long sum=0;
        for(int i=1;i<=R;i++)
        {
            int num;
            for(int j=1;j<=C;j++)
            {
                if(a[i][j]!=a[i][j-1]){
                    num=1;  S[1]=j-1;  h[i][j-1]=0;
                    S[++num]=j;
                    pos[j]=j-1;
                    ans[i][j]=h[i][j];
                    sum+=(long long)ans[i][j];
                    continue;
                }
                while(h[i][j]<=h[i][S[num]]) num--;
                pos[j]=S[num];
                S[++num]=j;
                ans[i][j]+=h[i][j]*(j-pos[j]);
                if(h[i][pos[j]]!=0)
                ans[i][j]+=ans[i][pos[j]];
                sum+=(long long)ans[i][j];
            }
        }
        printf("%lld\n",sum);
    }
    return 0;
}