View Compilation Error

0_0_36878138_19357.cpp: In function 'int main()':
0_0_36878138_19357.cpp:9:3: error: '_int64' was not declared in this scope
   _int64 n;
   ^
0_0_36878138_19357.cpp:10:18: error: 'n' was not declared in this scope
   scanf("%I64d",&n) ;
                  ^