View Compilation Error

0_0_36103912_25037.cpp: In function 'int main()':
0_0_36103912_25037.cpp:5:2: error: '_int64' was not declared in this scope
  _int64 x[50] = { 0,1 };
  ^
0_0_36103912_25037.cpp:6:32: error: 'x' was not declared in this scope
  for (int i = 2; i <= 50; i++) x[i] = x[i - 1] + x[i - 2];
                                ^
0_0_36103912_25037.cpp:11:12: error: 'x' was not declared in this scope
    cout << x[n] << endl;
            ^