View Compilation Error

0_0_22376674_16334.cpp: In function 'int main(int, char**)':
0_0_22376674_16334.cpp:37:2: error: expected initializer before 'long'
  long num;
  ^
0_0_22376674_16334.cpp:39:9: error: 'a' was not declared in this scope
  memset(a,-1, sizeof(a));
         ^
0_0_22376674_16334.cpp:43:17: error: 'num' was not declared in this scope
   scanf("%ld", &num);
                 ^