View Compilation Error

0_0_36812038_12842.cpp: In function 'int main()':
0_0_36812038_12842.cpp:47:6: error: 'f' was not declared in this scope
   if(f)printf("\n");
      ^
0_0_36812038_12842.cpp:48:3: error: 'f' was not declared in this scope
   f=1;
   ^