View Compilation Error

0_0_26321760_7605.cpp: In function 'void dfs(int, int)':
0_0_26321760_7605.cpp:83:22: error: return-statement with a value, in function returning 'void' [-fpermissive]
  if(pos==cnt) return 0;
                      ^
0_0_26321760_7605.cpp:86:2: error: 'flag' was not declared in this scope
  flag = 1;
  ^