View Compilation Error

0_0_31965548_1807.cpp: In function 'int main()':
0_0_31965548_1807.cpp:5:2: error: '_int64' was not declared in this scope
  _int64 a[50], n;
  ^
0_0_31965548_1807.cpp:6:2: error: 'a' was not declared in this scope
  a[0] = 0; a[1] = 1;
  ^
0_0_31965548_1807.cpp:7:16: error: 'n' was not declared in this scope
  while (cin >> n) {
                ^