Introduction - If you have any usage issues, please Google them yourself
Calculate and output the greatest common divisor (GCD) of a pair of integers.The classic algorithm for computing the GCD, known as Euclid’s algorithm, goes as follows: Let m and n be variables containing the two numbers. If n is 0, then stop: m contains the GCD.Use recursion.(There will be multiple input sets. The line contains two integer between 1 and 1000. For each test case, output one line.)