题目:
Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.
Note:
You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold additional elements from nums2. The number of elements initialized in nums1and nums2 are m and n respectively.
思路:
归并两个已经排序的数组,题目很简单。
从两个数组的末尾开始向前,将较大值添加到当前nums1的末端,并调整较大值所在数组的指针。
代码:
public class Solution {
public void merge(int[] nums1, int m, int[] nums2, int n) {
//处理特殊情况
if(nums2 == null || (m == 0 && n == 0)){return;}
if(nums1 == null){
nums1 = new int[n];
for(int t = 0; t < n; t++){
nums1[t] = nums2[t];
}
return;
}
//用两个指针放到两个数组的末端将较大的值放在nums1的最后
int p1 = m-1, p2 = n-1, i = m+n-1;
while(p1 >= 0 && p2 >= 0){
if(nums1[p1] > nums2[p2]){
nums1[i] = nums1[p1];
p1--;
}else{
nums1[i] = nums2[p2];
p2--;
}
i--;
}
//处理nums2还有数字的情况
if(p2 >= 0){
while(i >= 0){
nums1[i] = nums2[p2];
p2--;
i--;
}
}
}
}