#include <iostream>
/*
sortThree(a, b, c)
------------------
Sorts three numbers in ascending order using the simplest correct method.
Why this approach?
• For exactly three values, the minimal number of comparisons is three.
• Each comparison conditionally swaps two values.
• No loops, no arrays, no std::sort — extremely lightweight.
• Idiomatic: uses std::swap, which is clear and safe.
Algorithm:
1. Ensure a <= c
2. Ensure a <= b
3. Ensure b <= c
After these three steps, the values are sorted.
*/
void sortThree(int &a, int &b, int &c) {
if (a > c)
std::swap(a, c);
if (a > b)
std::swap(a, b);
if (b > c)
std::swap(b, c);
}
int main() {
int values[][3] = {
{3, 1, 2},
{10, 5, 7},
{100, 50, 75},
{9, 9, 1},
{42, 0, -5},
{8, 4, 4}
};
int count = sizeof(values) / sizeof(values[0]);
for (int i = 0; i < count; i++) {
int a = values[i][0];
int b = values[i][1];
int c = values[i][2];
sortThree(a, b, c);
std::cout << "sorted("
<< values[i][0] << ", "
<< values[i][1] << ", "
<< values[i][2] << ") = "
<< a << ", " << b << ", " << c << "\n";
}
}
/*
run:
sorted(3, 1, 2) = 1, 2, 3
sorted(10, 5, 7) = 5, 7, 10
sorted(100, 50, 75) = 50, 75, 100
sorted(9, 9, 1) = 1, 9, 9
sorted(42, 0, -5) = -5, 0, 42
sorted(8, 4, 4) = 4, 4, 8
*/
