View Compilation Error

0_0_38312613_15247.cpp: In function 'int main()':
0_0_38312613_15247.cpp:7:4: error: '_int64' was not declared in this scope
    _int64 sum;
    ^
0_0_38312613_15247.cpp:12:7: error: 'sum' was not declared in this scope
       sum=1;
       ^