要求:
import java.util.Random; import java.util.Scanner; public class Math2 { public static void main(String[] args) { // TODO Auto-generated method stub Scanner in=new Scanner(System.in); Random r = new Random(); int i,j,n; n=in.nextInt(); int size=1000; int [] a1=new int[size]; int [] a2=new int[size]; int [] t=new int[size]; for(i=0;i<n;i++) { a1[i]=r.nextInt(99)+1; a2[i]=r.nextInt(99)+1; t[i]=r.nextInt(100)%4; for(j=0;j<i;j++) { while(a1[i]==a1[j]&&a2[i]==a2[j]&&t[i]==t[j]) { //避免重复 t[i]=(t[i]*4+1)%4; a1[i]=r.nextInt(99)+1; a2[i]=r.nextInt(99)+1; } } switch(t[i]) { case 0:System.out.println(a1[i]+"+"+a2[i]+"=");break; case 1:System.out.println(a1[i]+"-"+a2[i]+"=");break; case 2:System.out.println(a1[i]+"*"+a2[i]+"=");break; case 3:System.out.println(a1[i]+"/"+a2[i]+"=");break; } } } }