(Java) Check array for increasing elements

Question

I\'m attempting to create a method that checks an array for increasing elements. True should be returned if all the elements are in increasing order. I get an out-of-bounds

Answer 1

You have two problems:

1. Your loop is one iteration too long: Because you are checking element i+1, i needs to finished incrementing one iteration earlier than a usual loop.
2. Your logic is flawed. Your loop will terminate the first time the check is true, so this array will pass: {1, 2, 0} when tested the first iteration tests 1 < 2 which is true, so return true - this is not what we want)

Fixing these two problems:

int[] one = {1,2,3,4,5};

public static boolean isIncreasing(int[] arr) {
    for(int i=0 ; i < arr.length - 1; i++) { // finish at length - 1
        if (arr[i] > arr[i+1]) {
            return false; // found elements that are out of order - return false
        }
    }    
    return true; // nothing out of order found - return true
}

This kind of logic - with an early exit with false on problem and a final return of true - is very common and a good pattern to learn.