题目:求1+2!+3!+...的前n项的和
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![]() | <span style="font-size:24px;BACKGROUND-COLOR: #ff0000"><strong>欢迎大家多提宝贵意见,我会仔细观看的:</strong></span> [java] import java.util.Scanner; /*题目:求1+2!+3!+...的前n项的和 1.程序分析:此程序只是把累加变成了累乘。*/ <span style="BACKGROUND-COLOR: #33ff33">public class Factorial { public static void main(String[]args){ int sum = 0; System.out.println("请输入多少项阶乘的和:"); Scanner in = new Scanner(System.in); int n = in.nextInt(); int an = 0; for(int i = 1;i <= n + 1;i++){ if(i == n + 1){ sum += an; }else if(i == n){ sum += an; an = 1; System.out.print(i+"!"); for(int j = i;j >= 1;j--){ an *=j; } }else if(i%10 == 0){ System.out.println(); sum += an; an = 1; System.out.print(i+"!"+"+"); for(int j = i;j >= 1;j--){ an *=j; } }else{ sum = sum + an; an = 1; System.out.print(i+"!"+"+"); for(int j = i;j >= 1;j--){ an *=j; } } }System.out.println(" = "+sum); } } </span> | |
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