View Compilation Error

2_15840_1099454_6461.cpp: In function `int main()':
2_15840_1099454_6461.cpp:5: error: `_int64' undeclared (first use this function)
2_15840_1099454_6461.cpp:5: error: (Each undeclared identifier is reported only once for each function it appears in.)
2_15840_1099454_6461.cpp:5: error: expected `;' before "a"
2_15840_1099454_6461.cpp:6: error: `a' undeclared (first use this function)
2_15840_1099454_6461.cpp:6: error: `b' undeclared (first use this function)
2_15840_1099454_6461.cpp:6: error: `c' undeclared (first use this function)
2_15840_1099454_6461.cpp:6: error: `n' undeclared (first use this function)
2_15840_1099454_6461.cpp:11: error: `i' undeclared (first use this function)
2_15840_1099454_6461.cpp:13: error: `k' undeclared (first use this function)