C++ bootcamp · Lab 27

Greatest common divisor

mediumFunctions12 minLesson: Functions

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QuestionHint and solution stay closed until you open them

Read two positive integers and print their greatest common divisor.

std::gcd lives in <numeric> (C++17). Euclid's loop is fine too.

Input. Two integers a and b.

Output. One integer: gcd(a, b).

Constraints

  • 1 ≤ a, b ≤ 1000000

Examples

Example 1
Input
48 18
Output
6
Example 2
Input
7 13
Output
1
Hint
  1. #include <numeric> then std::gcd(a, b).
  2. while (b) { int t = b; b = a % b; a = t; }
Show correct code

Peek only after you have tried. You can still Check your own version.

#include <iostream>
#include <numeric>

int main() {
  int a, b;
  std::cin >> a >> b;
  std::cout << std::gcd(a, b) << "\n";
  return 0;
}
main.cppC++17 · g++ · Ctrl + Enter runs
ResultIdle
Run to see output. Check grades the tests.