﻿ C Program: Determine the LCM of two numbers - w3resource

# C Exercises: Determine the LCM of two numbers

## C For Loop: Exercise-45 with Solution

Write a program in C to find LCM of any two numbers.

Pictorial Presentation:

Sample Solution:

C Code:

#include <stdio.h>

void main()
{
int i, n1, n2, max, lcm=1;

printf("\n\n  LCM of two numbers:\n ");
printf("----------------------\n");

printf("Input 1st number for LCM: ");
scanf("%d", &n1);
printf("Input 2nd number for LCM: ");
scanf("%d", &n2);

max = (n1>n2) ? n1 : n2;

for(i=max;  ; i+=max)
{

if(i%n1==0 && i%n2==0)
{
lcm = i;
break;
}
}

printf("\nLCM of %d and %d = %d\n\n", n1, n2, lcm);

}

Sample Output:

LCM of two numbers:
----------------------
Input 1st number for LCM: 15
Input 2nd number for LCM: 20

LCM of 15 and 20 = 60

Flowchart:

C Programming Code Editor:

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## C Programming: Tips of the Day

You are seeing the ffffff because char is signed on your system. In C, vararg functions such as printf will promote all integers smaller than int to int. Since char is an integer (8-bit signed integer in your case), your chars are being promoted to int via sign-extension.

Since c0 and 80 have a leading 1-bit (and are negative as an 8-bit integer), they are being sign-extended while the others in your sample don't.

char    int
c0 -> ffffffc0
80 -> ffffff80
61 -> 00000061
Here's a solution:
char ch = 0xC0;
printf("%x", ch & 0xff);

This will mask out the upper bits and keep only the lower 8 bits that you want.

Ref : https://bit.ly/3vOLizM