To show 25 images randomly out of 40 images in a grid view

Question

I am creating an iphone app in which I need to create a grid view of 25 images. I am doing that by taking 25 images in an array, and displaying them by using for loop by changin

Answer 1

Create an array of 41 numbers (0-40), shuffle them using a partial Fisher-Yates shuffle and use the first 25 elements of the array.

Pseudo-code (random(x) returns a random number from 0 to x inclusive):

array = [0, 1, 2, ..., 40]
for i in 0, 1, ..., 24 do
    swap array[i], array[i + random(40 - i)]
truncate array to 25 elements.