"Algorithm data structure Java implementation" binary lookup

1. Background

For example, an integer x is a set of numbers in a sequence of columns sorted by size, and we want to find the index position of x in the sequence.

For example, the sequence is arranged from small to large:

-3,-2,0,4,5,7,12,64

We want to find the position of the number 7, if it is a linear lookup, the time complexity is O (n), if you find with binary, the time complexity is O (log (n)), because each time the binary, the calculation of less than half, so take the logarithm.

2. Code

Package Algorithm_analysis;public class Bisearch {static int[] array={-3,-2,0,4,5,7,12,64}, public static void main ( String args[]) {   int left=0;   int right=array.length;   int center=0;   int k=7;     while (left<=right) {  center= (right+left)/2;   if ((array[center]-k) ==0) {  System.out.print (center);  break;   }   else{            if ((array[center]-k) >0) {                 right=center;            }                 else{                 Left=center;}}}}   Output Results 7

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"Algorithm data structure Java implementation" binary lookup