For each position, output the product of all the other elements of the array — without using division.
Line 1: an integer n.
Line 2: n integers.
n integers where the i-th is the product of every element except the i-th, space-separated.
Example 1
4 1 2 3 4
24 12 8 6
e.g. position 0 = 2·3·4 = 24.
Example 2
3 2 3 4
12 8 6
12, 8, 6.
Example 3
3 -1 1 0
0 0 -1
The zero makes two entries 0; the last is (-1)·1 = -1.
The answer at i is (product of everything to the left of i) × (product of everything to the right of i).
Compute a running prefix product left-to-right, then a running suffix product right-to-left.
Two passes: fill result[i] with the prefix product before i, then multiply by the suffix product after i. No division, handles zeros correctly.
import sys
d = list(map(int, sys.stdin.read().split()))
n = d[0]
a = d[1:1 + n]
res = [1] * n
pre = 1
for i in range(n):
res[i] = pre
pre *= a[i]
suf = 1
for i in range(n - 1, -1, -1):
res[i] *= suf
suf *= a[i]
print(' '.join(map(str, res)))
Tell us what needs to change, who it affects and any important deadline. We will review the context and reply with useful next questions.