View Compilation Error

0_0_4705002_22270.cpp: In function `int gao(int)':
0_0_4705002_22270.cpp:85: error: `x' undeclared (first use this function)
0_0_4705002_22270.cpp:85: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_4705002_22270.cpp:85: error: `y' undeclared (first use this function)
0_0_4705002_22270.cpp: In function `int main()':
0_0_4705002_22270.cpp:145: error: expected primary-expression before ']' token