View Compilation Error

0_0_7713506_24729.c:2: error: syntax error before "check1"
0_0_7713506_24729.c: In function `check1':
0_0_7713506_24729.c:24: error: `true' undeclared (first use in this function)
0_0_7713506_24729.c:24: error: (Each undeclared identifier is reported only once
0_0_7713506_24729.c:24: error: for each function it appears in.)
0_0_7713506_24729.c:25: error: `false' undeclared (first use in this function)
0_0_7713506_24729.c: At top level:
0_0_7713506_24729.c:27: error: syntax error before "check2"
0_0_7713506_24729.c: In function `check2':
0_0_7713506_24729.c:40: error: `true' undeclared (first use in this function)
0_0_7713506_24729.c:41: error: `false' undeclared (first use in this function)
0_0_7713506_24729.c: In function `main':
0_0_7713506_24729.c:57: error: `false' undeclared (first use in this function)