View Compilation Error

229810_0_13549.c:7: error: syntax error before '&' token
229810_0_13549.c: In function `Max_sum':
229810_0_13549.c:12: error: `n' undeclared (first use in this function)
229810_0_13549.c:12: error: (Each undeclared identifier is reported only once
229810_0_13549.c:12: error: for each function it appears in.)
229810_0_13549.c:14: error: `a' undeclared (first use in this function)
229810_0_13549.c:15: error: `p' undeclared (first use in this function)
229810_0_13549.c:17: error: `q' undeclared (first use in this function)
229810_0_13549.c: In function `main':
229810_0_13549.c:41: error: 'for' loop initial declaration used outside C99 mode
229810_0_13549.c:45: error: 'for' loop initial declaration used outside C99 mode