[Leetcode 31] 88 Merge Sorted Array
Problem:
Given two sorted integer arrays A and B, merge B into A as one sorted array.
Note:
You may assume that A has enough space to hold additional elements from B. The number of elements initialized in A and B are m and n respectively.
Analysis:
To finish the task efficiently, merge should started from the end of the two arrays.
Note, we can compute the total length of the new array by add A and B's separate length. Also remember to update the index of next elements to be merged
The time complexity is O(n+m), space complexity is O(n+m).
Code:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 class Solution { 2 public: 3 void merge(int A[], int m, int B[], int n) { 4 // Start typing your C/C++ solution below 5 // DO NOT write int main() function 6 int totalLen = m + n, aLast = m-1, bLast = n-1; 7 8 for (int i=m+n-1; i>=0; i--) { 9 if (aLast < 0) 10 A[i] = B[bLast--]; 11 else if (bLast < 0) 12 A[i] = A[aLast--]; 13 else 14 A[i] = (A[aLast] > B[bLast])?A[aLast--] : B[bLast--]; 15 } 16 } 17 };
Attention: