比如999=3*3*3*37
#include <stdio.h>void main (){int a,i;printf("please input a number/n");scanf("%d",&a);printf("%d=",a);for(i=2;i<=a;i++){for(i;i!=a;a=a/i){if(a%i==0)printf("%d*",i);else break;}}printf("%d",a);printf("/n");}