View Compilation Error

0_0_30399470_20710.cpp:4:1: error: expected ',' or ';' before 'int'
 int ans;
 ^
0_0_30399470_20710.cpp: In function 'int dfs(int, int)':
0_0_30399470_20710.cpp:14:13: error: 'ans' was not declared in this scope
   if(f==-1) ans+=res-2;
             ^
0_0_30399470_20710.cpp:15:8: error: 'ans' was not declared in this scope
   else ans+=res-1;
        ^
0_0_30399470_20710.cpp: In function 'int main()':
0_0_30399470_20710.cpp:24:3: error: 'ans' was not declared in this scope
   ans=0;
   ^