View Compilation Error

0_0_6130990_11833.cpp: In function `int main()':
0_0_6130990_11833.cpp:44: error: `a' undeclared (first use this function)
0_0_6130990_11833.cpp:44: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6130990_11833.cpp:44: error: `b' undeclared (first use this function)
0_0_6130990_11833.cpp:56: error: no match for 'operator>>' in 'std::cout >> "YES"'
0_0_6130990_11833.cpp:57: error: no match for 'operator>>' in 'std::cout >> "NO"'