随机数 加法运算题

#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;
int main(int argc, char** argv) {
	int shuliang,n1,n2,x,s,m=0;
	cout<<"输入你要做的题的数量\n"; 
	cin>>shuliang;
	for(int i=0;i<shuliang;i++){
		srand(time(0));
        	n1=rand()%100;
        	n2=rand()%100;
    	cout<<n1<<"+"<<n2<<"=?"<<endl;
    	x=n1+n2;
    	cin>>s;
    	if(s==x){
    		cout<<"正确"<<endl<<endl; 
    		m+=1;
		}else{
			cout<<"错误"<<endl<<endl; 
		}
	}
	cout<<"共"<<shuliang<<"道题"<<"你做对了"<<m<<"道题"<<endl; 
	if(m==shuliang){
		cout<<"太腻害了，全对了！";
	}else if(m>=shuliang*0.8){
		cout<<"不错呦"; 
	}else if(m>=shuliang*0.6&&m<shuliang*0.8){
		cout<<"一般"; 
	}else if(m<shuliang*0.6){
		cout<<"不及格哦"; 
	}
	return 0;
}