Question

Use Java or Javascript to slve

1. Given an array of numbers, write a function to return an array of numbers' where productsli] is the Input: [1, 2, 3,4, 5] Output: [(2*3*4*5), (1 3*4*5), (1*2*4*5), (1*2*3*5), (1*2*3*4)1 [120, 60, 40, 30, 24] You should do this in O(N) without using division.

Answer 1

Java code :

int[] product(int a[], int n)  

{

int prod[] = new int[n]; // making a product array ( n is the number of elements in the array)

for(int i=0;i<n;i++)

prod[i]=1; // Initialize this array elements with 1

int flag=1; // For left side product

for (int i=0;i<n;i++)  

{

prod[i] = flag; // flag will have productof all elements on left hand sisde excluding a[i]

flag = flag * a[i];

}

int temp = 1; // For right side product

for (int j=n-1;j>=0;j--)  

{

prod[j] = prod[j] * temp; // temp will have product of all elements on left hand sisde excluding a[j]

temp = temp * a[j];

}

return prod;

}