View Compilation Error

0_0_5171584_30088.c:3:20: algorithm: No such file or directory
0_0_5171584_30088.c:4: error: syntax error before "namespace"
0_0_5171584_30088.c:9: error: syntax error before "f"
0_0_5171584_30088.c:10: error: syntax error before "x"
0_0_5171584_30088.c: In function `cmp':
0_0_5171584_30088.c:12: error: `x' undeclared (first use in this function)
0_0_5171584_30088.c:12: error: (Each undeclared identifier is reported only once
0_0_5171584_30088.c:12: error: for each function it appears in.)
0_0_5171584_30088.c:12: error: `y' undeclared (first use in this function)