Thread: Can someone tell me why this code isn't working please?

EDIT!!

It doesn't even compile

it says:

/tmp/ccgGoNoC.o: In function `hypo':
hypotenuse.c.text+0x55): undefined reference to `sqrt'
collect2: ld returned 1 exit status

Code:

#include <stdio.h>
#include <math.h>

double hypo( double side1, double side2 )

{

        double answer;

        answer = sqrt( ( side1 * side1 ) + ( side2 * side2 ) );

        return answer;

}

int main ( int argc, char *argv[] )

{

        double sidea, sideb;

        printf( "enter side1: \n" );
        scanf( "%f", &sidea );

        printf( "enter side2: \n" );
        scanf( "%f", &sideb );

        printf( "the hypotenuse is: %lf.\n", hypo( sidea, sideb ) );
}

Code:

$ gcc -Wall bar.c -lm
bar.c: In function ‘main’:
bar.c:23: warning: format ‘%f’ expects type ‘float *’, but argument 2 has type ‘double *’
bar.c:26: warning: format ‘%f’ expects type ‘float *’, but argument 2 has type ‘double *’
bar.c:29: warning: control reaches end of non-void function

Try %lf instead.

Sounds like you need to link the math library, e.g., by passing -lm as a compiler option.

So I take it that you read NONE of my post.
Not only did you fail to replace %f with %lf, you also missed the -lm as well.