AcWing 787. 归并排序
原题链接
简单
Orlando 2024-10-24
import java.util.Scanner;
public class AC787 {
public static void main(String[] args){
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt(), array[] = new int[n];
for(int i = 0; i < n; i++)
array[i] = scanner.nextInt();
merge_sort(array, 0, n - 1);
for(int i = 0; i < n; i++)
System.out.print(array[i] + " ");
scanner.close();
}
private static void merge_sort(int[] array, int l, int r){
if(l >= r)
return;
int mid = l + r >> 1, tmp[] = new int[r - l + 1], i = l, j = mid + 1, k = 0;
merge_sort(array, l, mid);
merge_sort(array, mid + 1, r);
while (i <= mid && j <= r) {
if (array[i] <= array[j])
tmp[k++] = array[i++];
else
tmp[k++] = array[j++];
}
while(i <= mid)
tmp[k++] = array[i++];
while(j <= r)
tmp[k++] = array[j++];
for(int m = l, n = 0; m <= r;)
array[m++] = tmp[n++];
}
}