Given array of 0’s and 1’s. All 0’s are coming first followed by 1’s. find the position of first 1

Given array of 0’s and 1’s. All 0’s are coming first followed by 1’s. find the position of first 1

Example : 00001111
Output : 4Method 1 : in O(n) we can do it . with sequential search.

Method 2 : Binary search.

Yes binary search is useful, as data is sorted.
Just we need to change its conditions for 0 and 1.
lets have a look at Function firstOccurance.

firstOccurrance(int[] sortedBins) {
    int lower = 0;
    int upper = sortedBins.length - 1;
    while (lower <= upper) {
        int middle = 1 + (upper - lower) / 2;
        if (sortedBins[middle] == 0) {
            lower = middle + 1;
        } else {
            upper = middle - 1;
        } 
        if (sortedBins[lower] == 1) {
            return lower;
        }
    }
    return -1;
}