View Compilation Error

0_0_19783641_31519.cpp:7:1: error: expected initializer before 'int'
 int flag ; 
 ^
0_0_19783641_31519.cpp: In function 'void dfs(int, int, int)':
0_0_19783641_31519.cpp:10:7: error: 'vis' was not declared in this scope
    if(vis[i][j]) return ;
       ^
0_0_19783641_31519.cpp:11:4: error: 'vis' was not declared in this scope
    vis[i][j]=1 ; 
    ^
0_0_19783641_31519.cpp:12:21: error: 'flag' was not declared in this scope
    if(s3[k]=='\0')  flag=1 ;
                     ^
0_0_19783641_31519.cpp:13:7: error: 'flag' was not declared in this scope
    if(flag)  return ;
       ^
0_0_19783641_31519.cpp: In function 'int main()':
0_0_19783641_31519.cpp:33:13: error: 'vis' was not declared in this scope
      memset(vis,0,sizeof(vis)) ;
             ^
0_0_19783641_31519.cpp:35:4: error: 'flag' was not declared in this scope
    flag=0 ;
    ^