01串排序

#include <iostream>  
#include <vector>  
#include <algorithm>  
#include <string>  
using namespace std;
class String {
public:
    string str; 
    String(const string& s) : str(s) {}  
    int length() const {
        return str.length();
    }
    int countOnes() const {
        return count(str.begin(), str.end(), '1');
    }
    bool operator<(const String& other) const {
        if (length() != other.length()) {
            return length() < other.length();  
        }
        if (countOnes() != other.countOnes()) {
            return countOnes() < other.countOnes();  
        }
        return str < other.str;  
    }
}; 
struct StringComparator {
    bool operator()(const String& a, const String& b) {
        return a < b;
    }
};
int main() {
    vector<String> Strings;
    string s;
    while (getline(cin, s)) {
       Strings.emplace_back(s);
        if (s == "")break;
    }
    sort(Strings.begin(), Strings.end(), StringComparator());
    for (const auto& bs : Strings) {
        std::cout << bs.str << std::endl;
    }
    return 0;
}

运行结果：
 

按绩点排名 

#include <iostream>  
#include <vector>  
#include <algorithm>  
#include <iomanip>  
#include <string>  
using namespace std; 
class Student {
public:
    string name;
    double gpa;
    Student(string n, double g) : name(n), gpa(g) {}  
    bool operator<(const Student& other) const {
        if (gpa != other.gpa) {
            return gpa > other.gpa; 
        }
        else {
            return name < other.name; 
        }
    }
};
int main() {
    int classCount;
    cin >> classCount;
    for (int c = 1; c <= classCount; ++c) {
        int n, m;
        cin >> n;
        vector<int> credits(n);
        for (int i = 0; i < n; ++i) {
            cin >> credits[i];
        }
        cin >> m;
        vector<Student> students;
        for (int i = 0; i < m; ++i) {
            string name;
            vector<int> scores(n);
            cin >> name;
            for (int j = 0; j < n; ++j) {
                cin >> scores[j];
            }
            double gpa = 0.0;
            for (int j = 0; j < n; ++j) {
                if (scores[j] >= 60) {
                    gpa += (scores[j] - 50.0) / 10.0 * credits[j];
                }
            }
            gpa /= 10.0;
            students.emplace_back(name, gpa);
        }  
        sort(students.begin(), students.end()); 
        cout << "class " << c << ":" << endl;
        for (const auto& student : students) {
            cout << left << setw(10) << student.name << " " << 
                fixed << setprecision(2) << student.gpa << endl;
        }
        if (c < classCount) {
            cout << endl; 
        }
    }
    return 0;
}

运行结果：