声明函数sort为重载函数，并根据参数个数的不同分别进行定义；在main中用cin分别输入两个整数和三个整数；根据参数个数的不同，调用不同的函数，从而实现重载。

#include <iostream>
#include <algorithm>

using namespace std;

void sort(int &a, int &b) {
if (a > b) swap(a, b);
}

void sort(int &a, int &b, int &c) {
if (a > b) swap(a, b);
if (b > c) swap(b, c);
if (a > b) swap(a, b);
}

int main() {
int a, b, c;
cout << "Enter two integers: ";
cin >> a >> b;
sort(a, b);
cout << "The sorted integers are: " << a << " " << b << endl;
cout << "Enter three integers: ";
cin >> a >> b >> c;
sort(a, b, c);
cout << "The sorted integers are: " << a << " " << b << " " << c << endl;
return 0;
}