/in/foo.cc: In function 'int main()':
/in/foo.cc:18:7: warning: statement has no effect [-Wunused-value]
  for(k;k < n-1;k++){
       ^
/in/foo.cc:23:7: warning: statement has no effect [-Wunused-value]
  for(c;c < n-1;c++)
       ^