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C++ ????

1. ????

? C++ ?????????????????????????? <algorithm> ????? sort ??????????????

#include 
   
    
#include 
    
     
using namespace std;
bool cmp(int x, int y) {
    return x > y; // ????
}
int main() {
    int a[10];
    for (int i = 0; i < 10; i++) {
        cin >> a[i];
    }
    sort(a, a + 10); // ????
    for (int i = 0; i < 10; i++) {
        cout << a[i] << " ";
    }
    cout << endl;
    sort(a, a + 10, greater<>()); // ????
    for (int i = 0; i < 10; i++) {
        cout << a[i] << " ";
    }
    cout << endl;
}
    
   

?????????????????????? greater<>() ?????????

2. ?????

C++ ????????????????????????????????????

#include 
   
    
#include 
    
     
using namespace std;
struct Student {
    int score;
    string name;
    Student(string n, int s) : name(n), score(s) {}
};
int main() {
    Student stu[3];
    for (int i = 0; i < 3; i++) {
        string n;
        int s;
        cin >> n >> s;
        stu[i] = Student(n, s);
    }
    sort(stu, stu + 3, [](Student x, Student y) {
        return x.name < y.name;
    });
    for (int i = 0; i < 3; i++) {
        cout << stu[i].name << ":" << stu[i].score << " ";
    }
    cout << endl;
}
    
   

????????? Student ????????????????????

3. ?????

??????????????

#include 
   
    
#include 
    
     
#include 
     
      
using namespace std;
struct Student {
    string name;
    int score[4];
};
bool cmp(Student x, Student y) {
    if (x.score[0] != y.score[0]) {
        return x.score[0] > y.score[0];
    }
    if (x.score[1] != y.score[1]) {
        return x.score[1] > y.score[1];
    }
    if (x.score[2] != y.score[2]) {
        return x.score[2] > y.score[2];
    }
    return x.score[3] > y.score[3];
}
int main() {
    Student stu[3];
    for (int i = 0; i < 3; i++) {
        cin >> stu[i].name;
        for (int j = 0; j < 4; j++) {
            cin >> stu[i].score[j];
        }
    }
    sort(stu, stu + 3, cmp);
    for (int i = 0; i < 3; i++) {
        cout << stu[i].name << ":";
        for (int j = 0; j < 4; j++) {
            cout << stu[i].score[j] << " ";
        }
        cout << endl;
    }
}
     
    
   

?????????????????????

4. ?????

???????????????????????????????????

#include 
   
    
#include 
    
     
#include 
     
      
using namespace std;
const double ERSILON = 1e-6;
bool cmp(double a, double b) {
    double da = fabs(a - round(a));
    double db = fabs(b - round(b));
    if (fabs(da - db) < ERSILON) {
        return a < b;
    }
    return da < db;
}
int main() {
    int n;
    cin >> n;
    double num[n];
    for (int i = 0; i < n; i++) {
        cin >> num[i];
    }
    sort(num, num + n, cmp);
    for (int i = 0; i < n; i++) {
        cout << num[i] << " ";
    }
    cout << endl;
}
     
    
   

??????????????????????????

5. ????

?????????????

#include 
   
    
#include 
    
     
using namespace std;
int main() {
    int N, l1, r1, l2, r2;
    cin >> N >> l1 >> r1 >> l2 >> r2;
    int num[10005];
    for (int i = 0; i < N; i++) {
        cin >> num[i];
    }
    sort(num + l1 - 1, num + r2); // ??
    sort(num + l2 - 1, num + r2, greater<>()); // ??
    for (int i = 0; i < N; i++) {
        cout << num[i] << " ";
    }
    cout << endl;
}
    
   

???????????????????????????

6. Vector ?? Sort

? C++ ??vector ??? sort ?????????

#include 
   
    
#include 
    
     
#include 
     
      
using namespace std;
int main() {
    vector
      
        ve;
    for (int i = 10; i > 0; i--) {
        ve.push_back(i);
    }
    cout << "???-----";
    for (int i = 0; i < 10; i++) {
        cout << ve[i] << " ";
    }
    cout << endl;
    sort(ve.begin(), ve.end());
    cout << "???-----";
    for (int i = 0; i < 10; i++) {
        cout << ve[i] << " ";
    }
    cout << endl;
}
      
     
    
   

?????? sort ? vector ?????