北京理工大学复试上机--2003

#include <iostream>
#include <cmath>
using namespace std;
int main() {
    int x0, y0, z0, x, y, z;
    cout << "请输入球心坐标：";
    cin >> x0 >> y0 >> z0;
    cout << "请输入球上一点坐标：";
    cin >> x >> y >> z;
    double r = sqrt((x - x0) * (x - x0) + (y - y0) * (y - y0) + (z - z0) * (z - z0));
    cout << "球的半径为：" << r << endl;
    cout << "球的体积为：" << 3.14 * r * r * r * 4 / 3 << endl;
    return 0;
}

#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

struct student
{
    string no, name, sex;
    int age;
};

int main() {
    fstream ff("./test.txt");//这里ff就是指定的读写文件的一个“输入流”？  ， 反正是用它代替cin  要与后面cin区分开  仅为一个自定义名称  也可以用cin  但是后面真正cin就会报错！
    vector<student> s;
    student stu;
    
    while(ff >> stu.no >> stu.name >> stu.sex >> stu.age) {
        s.push_back(stu);        
    }
    ff.close();
    string no;
    cin >> no;
    for(int i = 0; i < s.size(); i++) {
        if(s[i].no == no) {
            cout << s[i].no << " " << s[i].name << " " << s[i].sex << " " << s[i].age << endl;
            break;
        }
    }
    return 0;
}

#include <iostream>
using namespace std;
int main() {
    int year, month, day;
    cout << "请输入年月日，空格隔开：" << endl;
    while(cin >> year >> month >> day) {
        int sum = 0;
        if(year % 400 == 0 || (year % 4 == 0 && year % 100 != 0)) {
            switch (month) {
                case 1 : sum += 0;break;
                case 2 : sum += 31;break;
                case 3 : sum += 60;break;
                case 4 : sum += 91;break;
                case 5 : sum += 121;break;
                case 6 : sum += 152;break;
                case 7 : sum += 182;break;
                case 8 : sum += 213;break;
                case 9 : sum += 244;break;
                case 10 : sum += 274;break;
                case 11 : sum += 305;break;
                case 12 : sum += 335;break;
            }
            sum += day;
        }
        else {
            switch (month) {
                case 1 : sum += 0;break;
                case 2 : sum += 31;break;
                case 3 : sum += 59;break;
                case 4 : sum += 90;break;
                case 5 : sum += 120;break;
                case 6 : sum += 151;break;
                case 7 : sum += 181;break;
                case 8 : sum += 212;break;
                case 9 : sum += 243;break;
                case 10 : sum += 273;break;
                case 11 : sum += 304;break;
                case 12 : sum += 334;break;
            }
            sum += day;
        }
        cout << year << "年" << month << "月" << day << "日是" << year << "年的第" << sum << "天" << endl;
    }
    return 0;
}