A program to find the LCM of two numbers?

Answer 1

/*

Assuming that by "a shell program", you mean "a program that is run from a shell", and not "a shell script", then this would fit the bill.

Note that it could be optimized in many ways, such as:

- checking only for prime factors

- only counting as high as the square root of the smaller number

*/

#include <stdio.h>

#include <stdlib.h>

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

int val1, val2, n, gcd = 0;

if( argc != 3 ){

fprintf( stderr, "Insufficent arguments. Syntax:\n\tgcf #a #b\n" );

fflush( stderr );

exit( 1 );

}

val1 = atoi( argv[1] );

val2 = atoi( argv[2] );

if( val1 < 2 val2 < 2 ){

printf( "No common factors\n" );

exit( 0 );

}

for( n = 2; n < val1 && n < val2; n++ ) {

if( val1 % n 0 ){

printf( "No common factors\n" );

}else{

printf( "Greatest common factor is %i\n", gcd );

}

return 0;

}