二分查找

#include <bits/stdc++.h>
using namespace std;
int main(int argc, char** argv) 
{
    int index=1;
    
    srand(time(0));
    int num=rand()%100;
    do{
        int n;
        cin>>n;
        if(n==num){
            cout<<"对了"<<endl;
            break; 
        } else if(n>num){
            cout<<"大了"<<endl;
        } else {
            cout<<"小了"<<endl;
        }
        index++; 
    }while(true);
    cout<<"用了"<<index<<"才打对"<<endl;
    return 0;
}