/in/foo.cc: In function 'int main()':
/in/foo.cc:19:6: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
      if(f[i])y=i;
      ^~
/in/foo.cc:20:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   b[i]=y;
   ^
/in/foo.cc:20:7: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   b[i]=y;
   ~~~~^~