Ⅰ 求第100到200的阶乘数之和的java程序
public class Factorial
{
public long fun(int n)
{
if(n==1||n==0)
return 1;
else return n*fun(n-1);
}
public static void main(String [ ] args)
{
long sum=0;
for(int i=100;i<=200;i++)
{
sum+=fun(i);
}
System.out.println("100到200的阶乘数之和是 "+sum);
}
}
Ⅱ c语言大整数乘法
#include<stdio.h>
#include<string.h>
void chengfa(char *a,char*b)
{
char c[10000];
int fuhao1,fuhao2;
if(a[0] == '-' || a[0] == '+') {
if(a[0] == '-')
fuhao1 = -1;
else fuhao1 = 1;
strcpy(c,a+1);
strcpy(a,c);
}
if(b[0] == '-' || b[0] == '+') {
if(b[0] == '-')
fuhao2 = -1;
else fuhao2 = 1;
strcpy(c,b+1);
strcpy(b,c);
}
int i , j;
for(i = 0; i< 10000;i++){
c[i] = '0';
}
int lena = strlen(a);
int lenb = strlen(b);
for(i = lena-1;i >=0;i--){
int k = 0;
for(j = lenb-1;j >=0;j--) {
char l = c[i+j+1];
c[i+j+1] = (c[i+j+1]-'0'+(b[j]-'0')*(a[i]-'0')+k)%10+'0';
k = (l-'0'+(b[j]-'0') * (a[i] -'0')+k)/10;
}
if(k!= 0) c[i] += k;
}
i = 0;
j = 0;
while(c[i] == '0') i++;
while(i <= lena+lenb-1) {
a[j] = c[i];
j ++;
i ++;
}
a[j] = '\0';
if(a[0] == '\0') a[0] = '0',a[1] = '\0';
if(fuhao1*fuhao2 == -1 && a[0] !='0') {
strcpy(c,a);
a[0] = '-';
a[1] = '\0';
strcat(a,c);
}
}
int main()
{
char a[10000],b[10000];
while(scanf("%s %s",a,b) == 2) {
chengfa(a,b);
printf("%s\n",a);
}
}
/*
//测试数据
3 4
12
1782362317836127863178 5
8911811589180639315890
2364782367834627864826 23478962483263478
*/
Ⅲ 求Java写的100的阶乘
100的阶乘int是存不了的，要用大数类：import java.math.BigDecimal;
public class Test {
public static void main(String args[]){
BigDecimal result= new BigDecimal(1);
for(int i=1;i<=100;i++){
BigDecimal i_value= new BigDecimal(i);
result = result.multiply(i_value);
}
System.out.println("result="+result);
}
}
Ⅳ 用java语言求100的阶乘
100的阶乘要用bigdecimal才可以
import java.math.BigDecimal;
public class Information {
public static void main(String[] args) {
BigDecimal bg = new BigDecimal(1L);
int i = 1;
while(i <= 100){
bg = bg.multiply(new BigDecimal(i++));
}
System.out.println(bg.toString());
}
}