[JAVA] Binary search method

I had the opportunity to write a 2-minute search, so I will write it as a memo.

What is a 2-minute search? The algorithm used when searching for data. You can continue the search while narrowing down the range of sorted data. A method for searching at high speed.

The 2-minute search is just an algorithm that searches while narrowing down the range by half from the entire array. Fast.


int algorithm(int[] data, int target) {
    int retrieve = -1;
    int left = 0;
    int right = data.length - 1;
    while(left < right){
        int mid = (left + right)/ 2;
        if(data[mid] == target){
            return mid + 1;
        }else if(target < data[mid]){
            return right = mid;
        }else {
            return left = mid + 1;
    return retrieve;

Summary If it's already sorted, it's better to do a 2-minute search.

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