1到20 阶乘和
1 ------------------------------------- 2 1、 3 #!/usr/bin/perl -w 4 $result=1; 5 $sum=0; 6 for($k=1;$k<=20;$k++){ 7 $result*=$k; 8 $sum+=$result; 9 } 10 printf("%.0f\n",$sum); 11 -----------------------------------------
2、 13 #!/usr/bin/perl 14 use List::Util qw(reduce sum); 15 printf ("%.0f\n",sum (map {reduce {$a * $b} 1 .. $_} 1 .. 20)); 16 -------------------------------------- 17 结果：2561327494111820300
