#include<bits/stdc++.h>
using namespace std;
long long a,b,c,d,x,n;
int main(){
	system("color 2A");
	srand(time(0));
	while(1){
		a=rand(),b=rand(),n=rand()%4+1;
		if(n==1){
			printf("%d+%d=?\n",a,b);
			cin>>c;
			if(c==a+b){
				x++;
				cout<<"正确！得分："<<x<<endl;
			} else{
				cout<<"错误！得分："<<x<<endl;
				return 0;
			}
		} else if(n==2){
			printf("%d-%d=?\n",a,b);
			cin>>c;
			if(c==a-b){
				x++;
				cout<<"正确！得分："<<x<<endl;
			} else{
				cout<<"错误！得分："<<x<<endl;
				return 0;
			}
		} else if(n==3){
			printf("%d*%d=?\n",a,b);
			cin>>c;
			if(x==-1)
				continue; 
			if(c==a*b){
				x++;
				cout<<"正确！得分："<<x<<endl;
			} else{
				cout<<"错误！得分："<<x<<endl;
				return 0;
			}
		} else{
			while(!b)
				b=rand();
			printf("%d/%d=?\n",a,b);
			cin>>c;
			if(c==a/b){
				x++;
				cout<<"正确！得分："<<x<<endl;
			} else{
				cout<<"错误！得分："<<x<<endl;
				return 0;
			}
		}
	}
	return 0;
}

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