View Compilation Error

0_0_38144385_8517.c: In function 'main':
0_0_38144385_8517.c:21:3: error: expected expression before '/' token
   //n=c;
   ^
0_0_38144385_8517.c:22:3: error: expected expression before '/' token
   //a--;
   ^
0_0_38144385_8517.c:23:6: error: expected expression before '/' token
      //printf("%d",o);
      ^
0_0_38144385_8517.c:29:2: error: expected expression before '/' token
  //printf("%d",o);
  ^