View Compilation Error

154678_0_8762.c: In function `main':
154678_0_8762.c:6: error: syntax error before "unsigned"
154678_0_8762.c:9: error: `sum' undeclared (first use in this function)
154678_0_8762.c:9: error: (Each undeclared identifier is reported only once
154678_0_8762.c:9: error: for each function it appears in.)