Given an array of n integers where n > 1, nums,
return an array output such that output[i] is
equal to the product of all the elements of nums except nums[i].
Solve it without division and in O(n).
For example, given [1,2,3,4],
return [24,12,8,6].
Follow up:
Could you solve it with constant space complexity? (Note: The output array does not count as extra space for the purpose of space complexity analysis.)
Show Similar Problems
Have you met this question in a real interview?
Silu: Using ret[i] = ret[i - 1] * nums[i - 1]. It has storage the previous element production. Then, we use a temp number to storage the tail elements production.
public class Solution {
public int[] productExceptSelf(int[] nums) {
int[] ret = new int[nums.length];
if(nums.length < 1)
return ret;
ret[0] = 1;
for(int i = 1; i < nums.length; i++){
ret[i] = ret[i - 1] * nums[i - 1];
}
for(int i = nums.length - 1, temp = 1; i >= 0; i--){
ret[i] = ret[i] * temp;
temp *= nums[i];
}
return ret;
}
}