View Compilation Error

0_0_6265937_10943.cpp: In function `int main()':
0_0_6265937_10943.cpp:5: error: `_int64' undeclared (first use this function)
0_0_6265937_10943.cpp:5: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6265937_10943.cpp:5: error: expected `;' before "f"
0_0_6265937_10943.cpp:6: error: `f' undeclared (first use this function)