Program compiles on one server, doesn't on another

I'm getting this error when I try and compile my program on my school's external server.

Undefined                       first referenced
 symbol                             in file
pow                                 /var/tmp//ccWbipvM.o
sqrt                                /var/tmp//开发者_如何学JAVAccWbipvM.o
ld: fatal: Symbol referencing errors. No output written to assign1
collect2: ld returned 1 exit status

The problem is I don't get it when I compile it locally - it runs fine. Can anyone give me some advice as to what the problem is here?? Thanks!

PS: math.h has been included.

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Try linking your program with the math library by using the -lm flag:

gcc -o prg -lm prg.c