The problem

Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.

Example:

Input: [-2,1,-3,4,-1,2,1,-5,4],
Output: 6
Explanation: [4,-1,2,1] has the largest sum = 6.

The code

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// This method takes an array of `ints` and returns an `int`
public int maxSubArray(int[] nums) {
    // Set some `max` variables,
    // ..firstly the minimum `Integer` value
    // ..secondly `0`
    int max = Integer.MIN_VALUE;
    int iMax = 0;

    // Loop through all input `nums`
    for(int num : nums) {
        // increment the `iMax` each loop
        iMax = iMax + num;
        // check if `num` is bigger than `iMax`
        if(iMax < num) {
            // set `iMax` to the `num`
            iMax = num;
        }
        // set the `max` to the max of both our variables
        max = Math.max(max,iMax);
    }
    // return the `max`
    return max;
}