https://en.wikipedia.org/wiki/Selection_sort
loop1:
4,6,1,3,7 -> 4,6,1,3,7
4,6,1,3,7 -> 1,6,,3,7
1,6,4,3,7 -> 1,6,4,3,7
1,6,4,3,7 -> 1,6,4,3,7
loop2:
1,6,4,3,7 -> 1,4,6,3,7
1,4,6,3,7 -> 1,3,6,,7
1,3,6,4,7 -> 1,3,6,4,7
loop3:
1,3,6,4,7 -> 1,3,4,6,7
1,3,4,6,7 -> 1,3,4,6,7
loop4:
1,3,4,6,7 -> 1,3,4,6,7
package sorting;
import java.util.Arrays;
import org.junit.Test;
public class SelectionSorting {
int[] items = { 4, 6, 1, 3, 7 };
int step = 0;
// ① 相邻
// ② 差一步
// ③ n个数可产生 n-1 对
// ④ 逐块收复失地
@Test
public void sort() {
for (int i = 0; i < items.length - 1; i++) {
for (int j = i + 1; j < items.length; j++) {
step++;
if (items[i] > items[j]) {
swap(i, j);
}
}
}
System.out.println(step + ":" + Arrays.toString(items));
}
public void swap(int i, int j) {
int backup = items[i];
items[i] = items[j];
items[j] = backup;
}
}