View Compilation Error

0_0_3875453_7696.cpp: In function `int main()':
0_0_3875453_7696.cpp:8: error: `_int64' undeclared (first use this function)
0_0_3875453_7696.cpp:8: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_3875453_7696.cpp:8: error: expected `;' before "first"
0_0_3875453_7696.cpp:18: error: `first' undeclared (first use this function)
0_0_3875453_7696.cpp:18: error: `second' undeclared (first use this function)
0_0_3875453_7696.cpp:27: error: `ans' undeclared (first use this function)