Main.cc: In function 'int main()':
Main.cc:20:21: error: 'cn1' was not declared in this scope
printf("%.2lf%%\n",cn1/n*100);
^
Main.cc:21:21: error: 'cn2' was not declared in this scope
printf("%.2lf%%\n",cn2/n*100);
^
Main.cc:22:21: error: 'cn3' was not declared in this scope
printf("%.2lf%%\n",cn3/n*100);
^
Main.cc:23:21: error: 'cn4' was not declared in this scope
printf("%.2lf%%\n",cn4/n*100);
^