详解C++ sort函数的cmp参数

void std::sort()

Sort the elements of a sequence using a predicate for comparison.

参数:
__first – An iterator.
__last – Another iterator.
__comp – A comparison functor.

Copy Line-numbers language-cpp
#include <iostream>
#include <algorithm>
using namespace std;
int main() {
    int a[5] = {2, 1, 3, 5, 4};
    sort(a, a + 5);
    for (int i = 0; i < 5; i++) cout << a[i] << " ";
}

a + 0
a + 1
a + 2
a + 3
a + 4

#include <iostream>
#include <algorithm>
using namespace std;

bool cmp(int x, int y){
    return x > y;
}

int main() {
    int a[5] = {2, 1, 3, 5, 4};
    sort(a, a + 5, cmp);
    for (int i = 0; i < 5; i++) cout << a[i] << " ";
}

Yixiangzhilv 90
Mydr 60
Xiaoming 10
Mr.Glass 60
GZN 80
Wangzi 85
Hyx 100
Wyx 99
Xth 0
Zz 75

#include <algorithm>
#include <iostream>
using namespace std;

struct node {
    string name;
    int score;
};

bool cmp(struct node x, struct node y) {
    return x.score > y.score;
}

int main() {
    struct node a[10];
    for (int i = 0; i < 10; i++) cin >> a[i].name >> a[i].score;
    sort(a, a + 10, cmp);
    for (int i = 0; i < 10; i++) cout << a[i].name << " " << a[i].score << endl;
}