PHP nCr()

1 개요

PHP nCr()

<?php
function nCr($n, $r) {
    if( $r > $n ) return -1;
    if( $r == 0 ) return 1;
    if( $n == $r ) return 1;
    return nCr($n-1,$r)+nCr($n-1,$r-1);
}
echo nCr(1,2) . PHP_EOL;
echo nCr(2,2) . PHP_EOL;
echo nCr(3,2) . PHP_EOL;
echo nCr(4,2) . PHP_EOL;
echo nCr(5,2) . PHP_EOL;
echo nCr(52,5) . PHP_EOL;
# -1
# 1
# 3
# 6
# 10
# 2598960

2 같이 보기

• 함수 nCr()