Binary Search

Binary Search

- (NSInteger)binarySearch:(id)object inArray:(NSArray *)array {
    
    NSInteger minIndex = 0;
    NSInteger maxIndex = [array count] - 1;
    
    while (maxIndex >= minIndex) {
        NSInteger midIndex = (maxIndex + minIndex) / 2;
        
        if ([array[midIndex] compare:object] == NSOrderedAscending) {
            minIndex = midIndex + 1;
        } else if ([array[midIndex] compare:object] == NSOrderedDescending) {
            maxIndex = midIndex - 1;
        } else {
            return midIndex;
        }
    }
    
    return NSNotFound;
}