View Compilation Error

0_0_3068323_9578.c: In function `main':
0_0_3068323_9578.c:9: error: `HP' undeclared (first use in this function)
0_0_3068323_9578.c:9: error: (Each undeclared identifier is reported only once
0_0_3068323_9578.c:9: error: for each function it appears in.)
0_0_3068323_9578.c:9: error: syntax error before "a"
0_0_3068323_9578.c:11: error: `a' undeclared (first use in this function)