View Compilation Error

0_0_36505073_3340.cpp: In function 'int main()':
0_0_36505073_3340.cpp:17:5: error: 'int64_t' was not declared in this scope
     int64_t all = n * (n + 1) * m * (m + 1) / 4;
     ^
0_0_36505073_3340.cpp:18:13: error: expected ';' before 'ans'
     int64_t ans = 0;
             ^
0_0_36505073_3340.cpp:23:17: error: expected ';' before 'res'
         int64_t res = 0;
                 ^
0_0_36505073_3340.cpp:38:11: error: 'res' was not declared in this scope
           res += (n - i + 1) * (j - l + 1) * (r - j + 1);
           ^
0_0_36505073_3340.cpp:40:9: error: 'ans' was not declared in this scope
         ans += res;
         ^
0_0_36505073_3340.cpp:40:16: error: 'res' was not declared in this scope
         ans += res;
                ^
0_0_36505073_3340.cpp:42:31: error: 'ans' was not declared in this scope
     printf("%.9Lf\n", (real_t)ans / all);
                               ^
0_0_36505073_3340.cpp:42:37: error: 'all' was not declared in this scope
     printf("%.9Lf\n", (real_t)ans / all);
                                     ^