Problem A. Dynamic Grid Google APAC 2016 University Test Round D

#include<iostream>
#include<stdio.h>
#include<cstdio>
#include<string>
#include<cmath>
#include<stdlib.h>
#include<algorithm>
#include<string.h>
#include<cstring>
#include<vector>
#include<queue>
#include<map>
#include<set>

using namespace std;

//2016 Round D Problem A. Dynamic Grid
int T;
const int maxn=110;
int N;
int R;
int C;
int mp[maxn][maxn];
bool vis[maxn][maxn];
int x;
int y;
int z;
char op;
int ans;
int dx[]={0,-1,0,1};
int dy[]={-1,0,1,0};
void bfs(int stx,int sty)
{
queue<pair<int,int> >que;
while(!que.empty()) que.pop();
que.push(make_pair(stx,sty));

while(!que.empty())
{
pair<int,int>now;
now=que.front();
que.pop();
vis[now.first][now.second]=true;
for(int d=0;d<4;d++)
{
int nextx=now.first+dx[d];
int nexty=now.second+dy[d];
if(nextx<0||nextx>=R||nexty<0||nexty>=C)
{
continue;
}
if(mp[nextx][nexty]==0) continue;
if(vis[nextx][nexty]==true) continue;
que.push(make_pair(nextx,nexty));
}
}
ans++;
}
int main()
{
freopen("A-large-practice.in","r",stdin);
//    freopen("input.txt","r",stdin);
freopen("output.txt","w",stdout);
scanf("%d",&T);
for(int ca=1;ca<=T;ca++)
{
printf("Case #%d:\n",ca);
memset(mp,0,sizeof(mp));
memset(vis,false,sizeof(vis));
scanf("%d %d",&R,&C);
for(int i=0;i<R;i++)
{
char tmpc[maxn];
scanf("%s",&tmpc);
for(int j=0;j<C;j++)
{
mp[i][j]=tmpc[j]-'0';
//                if(tmpc=='0')
//                {
//                    mp[i][j]=0;
//                }
//                else if(tmpc=='1')
//                {
//                    mp[i][j]=1;
//                }
//scanf("%d",&mp[i][j]);
//cout<<mp[i][j]<<" ";
}
//cout<<endl;
}

scanf("%d",&N);
//cout<<N<<endl;
//return 0;
for(int i=0;i<N;i++)
{
cin>>op;//scanf("%c",&op);
//cout<<"st"<<op<<"ed"<<endl;
if(op=='Q')
{
ans=0;
memset(vis,false,sizeof(vis));
for(int i=0;i<R;i++)
{
for(int j=0;j<C;j++)
{
if(mp[i][j]==0||vis[i][j]==true)
{
continue;
}
bfs(i,j);
}
}
printf("%d\n",ans);
}
else if(op=='M')
{
scanf("%d %d %d",&x,&y,&z);
//cout<<x<<" "<<y<<" "<<z<<endl;
mp[x][y]=z;
}
}

//printf("Case #%d: %d\n",ca,dp[N-1][Q]);

}
return 0;
}