题目来源：问题 A: Least Common Multiple 题目描述 The least common multiple (LCM) of a set of positive integers is the smallest positive integer which is divisible by all the numbers in the set. For example, the LCM of 5, 7 and 15 is 105.
输入 Input will consist of multiple problem instances. The first line of the input will contain a single integer indicating the number of problem instances. Each instance will consist of a single line of the form m n1 n2 n3 … nm where m is the number of integers in the set and n1 … nm are the integers. All integers will be positive and lie within the range of a 32-bit integer.
输出 For each problem instance, output a single line containing the corresponding LCM. All results will lie in the range of a 32-bit integer.
样例输入 2 2 3 5 3 4 6 12 样例输出 15 12
#include <iostream> #include <cmath> using namespace std; int gcd(int a, int b) //计算最大公约数 { if (b == 0) { return a; } else { return gcd(b, a % b); } } int lcm(int a, int b) //计算最小公倍数 { return a / gcd(a, b) * b; //lcm = a*b / gcd(a,b),调换位置是害怕a*b溢出 } int main() { int n; cin >> n; while (n--) { int m; cin >> m; int a, b; if (m == 1) { cin >> a; cout << a << endl; continue; } else { cin >> a >> b; a = lcm(a, b); for (int i = 2; i < m; i++) { cin >> b; a = lcm(a, b); } } cout << a << endl; } return 0; }