Find GCD and LCM Using C Program

Key Architecture Takeaways

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  Point 1: Core computer science and engineering computing concept: Find GCD and LCM Using C Program.
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  Point 2: Detailed trace of memory representation, algorithmic complexity, and control structures.
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  Point 3: Includes portable ISO C (C17/C23) code examples verified with modern GCC and Clang.

> gcc -Wall -Wextra -O2 program.c -o program
> ./program
> ```


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**GCD:** The *greatest common divisor* (GCD), which is also known as the *greatest common factor* (GCF), of two or more integers, is the largest integer that is a common divisor (factor) of all the given integers.

**LCM: **The *least common multiple* (LCM), which is also known as the *least common denominator* (LCD) in fractions, of two or more integers is the smallest integer that is a common multiple (denominator) of all the given integers.

## C program to find GCD & LCM

c #include<stdio.h>

int main() { int a, b, x, y, tmp, lcm, gcd;

printf("Enter two integers\n"); scanf("%d%d", &x, &y);

a = x; //Assign value of x to a for farther use. b = y; //Assign value of y to b for farther use.

while (b != 0) { tmp = b; b = a % b; a = tmp; }

gcd = a; lcm = (x*y)/gcd;

printf("Greatest common divisor of %d and %d is = %d\n", x, y, gcd); printf("Least common multiple of %d and %d is = %d\n", x, y, lcm);

return 0; }

## C program to find LCM and HCF of two numbers using recursion

c / C Program to find GCD and LCM of two numbers using recursion */ #include <stdio.h> #include <conio.h>

int getGcd(int a, int b); int main(){ int num1, num2, gcd, lcm; textcolor(BLUE+BLINK); cprintf("Enter two numbers\n"); cscanf("%d %d", &num1, &num2); / GCD(a, b) LCM(a, b) = ab / gcd = getGcd(num1, num2); lcm = (num1 num2)/ gcd; textcolor(RED); cprintf("GCD of %d and %d is %d\n", num1, num2, gcd); cprintf("LCM of %d and %d is %d\n", num1, num2, lcm); getch(); return 0; } / Function to calculate Greatest Common Divisor of two number */ int getGcd(int a, int b) { if (b == 0) { return a; } else { return getGcd(b, a % b); } }

Output

GCD LCM