View Compilation Error

0_0_13854789_32027.cpp:11:1: error: '_int64' does not name a type
 _int64 f[maxn], p[maxn], ans, tot, sum;  
 ^
0_0_13854789_32027.cpp: In function 'void get()':
0_0_13854789_32027.cpp:15:5: error: 'p' was not declared in this scope
     p[0] = 1;  
     ^
0_0_13854789_32027.cpp:18:9: error: 'f' was not declared in this scope
         f[i] = (i * f[i - 1] + p[i - 1] * i * (i - 1) / 2) % base;  
         ^
0_0_13854789_32027.cpp: In function 'int main()':
0_0_13854789_32027.cpp:28:9: error: 'ans' was not declared in this scope
         ans = tot = 0;  
         ^
0_0_13854789_32027.cpp:28:15: error: 'tot' was not declared in this scope
         ans = tot = 0;  
               ^
0_0_13854789_32027.cpp:32:13: error: 'sum' was not declared in this scope
             sum = 0;  
             ^
0_0_13854789_32027.cpp:36:24: error: 'f' was not declared in this scope
                (ans += f[n - i] + p[n - i] * (tot+sum)) %= base;  
                        ^
0_0_13854789_32027.cpp:36:35: error: 'p' was not declared in this scope
                (ans += f[n - i] + p[n - i] * (tot+sum)) %= base;  
                                   ^