Find gcd and lcm of two numbers?

Short answer: public int GCD(int a, int b) { Follow on: while (b != 0) { int temp = b; b = a % b; a = temp; } return a; } public int LCM(int a, int b) { return (a / GCD(a, b)) * b; } Explanation: GCD uses Euclidean algorithm. LCM calculated via LCM(a,b) = (a*b)/GCD(a,b).

Example code

public int GCD(int a, int b) { Follow on: while (b != 0) { int temp = b;
b = a % b;
a = temp;
}
return a;
}
public int LCM(int a, int b) {
return (a / GCD(a, b)) * b;
} Explanation: GCD uses Euclidean algorithm. LCM calculated via LCM(a,b) = (a*b)/GCD(a,b).

Real-world example (ShopNest)

In coding rounds, state complexity aloud, write a clear ShopNest-flavored example (orders, carts), then handle edge cases (empty list, null, overflow).

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.