当n = m时,C(n, m) = C(n, n) = 1。

This commit is contained in:
刘生平
2021-08-26 21:05:07 +08:00
parent ea976bc25b
commit ad5bba2703

View File

@@ -38,12 +38,9 @@ public class Combination implements Serializable {
* @return 组合数
*/
public static long count(int n, int m) {
if (0 == m) {
if (0 == m || n == m) {
return 1;
}
if (n == m) {
return NumberUtil.factorial(n) / NumberUtil.factorial(m);
}
return (n > m) ? NumberUtil.factorial(n, n - m) / NumberUtil.factorial(m) : 0;
}