View Compilation Error

0_0_33146144_467.cpp: In function 'll sum(int)':
0_0_33146144_467.cpp:18:2: error: return-statement with no value, in function returning 'll {aka long long int}' [-fpermissive]
  return ;
  ^
0_0_33146144_467.cpp: In function 'int main()':
0_0_33146144_467.cpp:43:5: error: expected '(' at end of input
     if 
     ^
0_0_33146144_467.cpp:43:5: error: expected '}' at end of input
0_0_33146144_467.cpp:43:5: error: expected '}' at end of input
0_0_33146144_467.cpp:43:5: error: expected '}' at end of input
0_0_33146144_467.cpp:43:5: error: expected '}' at end of input