https://www.nowcoder.com/practice/02d8d42b197646a5bbd0a98785bb3a34?tpId=85&&tqId=29857&rp=1&ru=/activity/oj&qru=/ta/2017test/question-ranking

#include <iostream>
using namespace std;

int main()
{
    int a, b, c, d;
    cin>>a>>b>>c>>d;

    int A=(a+c)/2;
    int B1=(b+d)/2;
    int C=(d-b)/2;
    int B2=(c-a)/2;
    if(B1!=B2)
        cout<<"No"<<endl;
    else
        cout<<A<<' '<<B1<<' '<<C<<endl;
    return 0;
}


https://www.nowcoder.com/practice/ac61207721a34b74b06597fe6eb67c52?tpId=85&&tqId=29862&rp=1&ru=/activity/oj&qru=/ta/2017test/question-ranking

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
char point[]="0123456789ABCDEF";

int main()
{
    int m,n;
    cin>>m>>n;

    char flag='+'; //标记正负
    if(m==0)
    {
        cout<<m<<endl;
    }

    if(m<0)
    {
        flag='-';
        m=-m;
    }

    string s; //存
    while(m)
    {
        int tmp = m%n;
        s+=point[tmp];
        m/=n;
    }
    if(flag=='-')
        cout<<'-';
    reverse(s.begin(), s.end());
    cout<<s<<endl;


    return 0;
}