View Compilation Error

0_0_39383228_7936.cpp: In function 'int main()':
0_0_39383228_7936.cpp:6:9: error: '_int64' was not declared in this scope
    6 |         _int64 arr[21];
      |         ^~~~~~
0_0_39383228_7936.cpp:8:9: error: 'arr' was not declared in this scope
    8 |         arr[1]=0;arr[2]=1;
      |         ^~~