定义一个结构体数组存放五位学生的学号，姓名以及3门课程的成绩，编写程序从屏幕输入这五位学生的信息，对次数组按总分进行排序再打印排序后的学生信息。

以下是一个解决该问题的C++代码示例：

#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

struct Student {
    string id;
    string name;
    int scores[3];
    int totalScore;
};

bool compare(Student a, Student b) {
    return a.totalScore > b.totalScore;
}

int main() {
    Student students[5];
    for (int i = 0; i < 5; i++) {
        cout << "请输入第" << i+1 << "位学生的信息：" << endl;
        cout << "学号：";
        cin >> students[i].id;
        cout << "姓名：";
        cin >> students[i].name;
        cout << "3门课程的成绩：";
        for (int j = 0; j < 3; j++) {
            cin >> students[i].scores[j];
            students[i].totalScore += students[i].scores[j];
        }
    }

    sort(students, students+5, compare);

    cout << "按总分排序后的学生信息：" << endl;
    for (int i = 0; i < 5; i++) {
        cout << "学号：" << students[i].id << endl;
        cout << "姓名：" << students[i].name << endl;
        cout << "3门课程的成绩：";
        for (int j = 0; j < 3; j++) {
            cout << students[i].scores[j] << " ";
        }
        cout << endl;
        cout << "总分：" << students[i].totalScore << endl;
        cout << endl;
    }

    return 0;
}

运行程序后，输入5位学生的信息，程序将按总分排序后输出学生信息。