because 3²+4²=5², So it's called '3,4,5' Is the number of shares , seek n( Include n) Array of all Pythagorean numbers within .

such as ：10 Within the Pythagorean array :['3,4,5','6,7,8']

Catalog

One 、 Topic analysis

Two 、 Program code

3、 ... and 、 Running results

One 、 Topic analysis

We've all learned Pythagorean theorem , Know that Pythagorean theorem needs to meet a²+b²=c², We can split the two sides of the equation , First

Traverse once 1~n, Storage c Square result set of , And then through the double layer for Cycle calculation a²+b², Finally, judge a²+b² Are and in c In the square result set of , If in , Just explain ,a,b,c Satisfy the Pythagorean number relationship .

Two 、 Program code

package com;

import java.util.ArrayList;
import java.util.List;

public class Main {

	public static void main(String[] args) {
		int n = 10;
		List<Integer> zList = new ArrayList<>();
		for (int i = 1; i <= n; i++) {
			zList.add(i * i);
		}
		List<String> result = new ArrayList<>();
		for (int x = 1; x < n; x++) {
			for (int y = x; y < n; y++) {
				int z = x * x + y * y;
				if (zList.contains(z)) {
					result.add(String.format("'%d,%d,%d'", x, y, (int) Math.sqrt(z)));
				}
			}
		}
		System.out.println(result);
	}

}

3、 ... and 、 Running results