用递归求三个数的最大公约数，，，好难啊，，怎么求，，我新手啊，，想了半天
老班的题目啊： 声明求最大公约数的递归方法，写出求两个整数a,b的最小公倍数、三个整数最大公约数的调用语句。
程序代码：
public class GCD_LCM {
public static void main(String[] args) {
int a = 0;
int b = 0;
int c = 0;
a = 1; b = 2; c = 3;
System.out.println(a + " " + b + " " + c + "'s gcd:" + gcd(a, b, c));
System.out.println(a + " " + b + "'s lcm:" + lcm(a, b));
a = 10; b = 20; c = 30;
System.out.println(a + " " + b + " " + c + "'s gcd:" + gcd(a, b, c));
System.out.println(a + " " + b + "'s lcm:" + lcm(a, b));
}
public static int gcd(int a, int b, int c) { // Greatest Common Divisor
return gcd(gcd(a, b), c);
}
public static int gcd(int a, int b) { // Greatest Common Divisor
if (a == 0) {
return b;
} else {
while (b != 0) {
if (a > b) {
a = a - b;
} else {
b = b - a;
}
}
return a;
}
}
public static int lcm(int a, int b) { // Least Common Multiple
return a * b / gcd(a, b);
}
}
输出：
1 2 3's gcd:1
1 2's lcm:2
10 20 30's gcd:10
10 20's lcm:20