View Compilation Error

0_0_8632681_9316.c:6: error: syntax error before ';' token
0_0_8632681_9316.c: In function `add':
0_0_8632681_9316.c:11: error: `d' undeclared (first use in this function)
0_0_8632681_9316.c:11: error: (Each undeclared identifier is reported only once
0_0_8632681_9316.c:11: error: for each function it appears in.)
0_0_8632681_9316.c: In function `query':
0_0_8632681_9316.c:17: error: `d' undeclared (first use in this function)
0_0_8632681_9316.c: In function `main':
0_0_8632681_9316.c:27: error: `d' undeclared (first use in this function)
0_0_8632681_9316.c:31: error: `a' undeclared (first use in this function)