View Compilation Error

569811_0_0_11892.cpp: In function `int main()':
569811_0_0_11892.cpp:4: error: `_int64' undeclared (first use this function)
569811_0_0_11892.cpp:4: error: (Each undeclared identifier is reported only once for each function it appears in.)
569811_0_0_11892.cpp:4: error: expected `;' before "n"
569811_0_0_11892.cpp:5: error: `n' undeclared (first use this function)
569811_0_0_11892.cpp:6: error: `a' undeclared (first use this function)
569811_0_0_11892.cpp:7: error: `b' undeclared (first use this function)