View Compilation Error

0_0_38423393_6361.cpp: In function 'int main()':
0_0_38423393_6361.cpp:13:15: error: return-statement with no value, in function returning 'int' [-fpermissive]
 if(n<0||n>50) return;
               ^
0_0_38423393_6361.cpp:20:15: error: 'flsg' was not declared in this scope
  if(score<60) flsg=1;
               ^