View Compilation Error

0_0_10088971_14874.cpp: In function `int main()':
0_0_10088971_14874.cpp:16: error: `_int64' undeclared (first use this function)
0_0_10088971_14874.cpp:16: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_10088971_14874.cpp:16: error: expected `;' before "res"
0_0_10088971_14874.cpp:21: error: `res' undeclared (first use this function)