40 lines
1.1 KiB
Java
40 lines
1.1 KiB
Java
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/* this Code is the illustration of Boyer moore's voting algorithm to
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find the majority element is an array that appears more than n/2 times in an array
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where "n" is the length of the array.
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For more information on the algorithm refer https://en.wikipedia.org/wiki/Boyer%E2%80%93Moore_majority_vote_algorithm
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*/
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package Others;
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import java.util.*;
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public class BoyerMoore {
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public static int findmajor(int [] a){
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int count=0; int cand=-1;
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for(int i=0;i<a.length;i++){
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if(count==0){
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cand=a[i];
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count=1;
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}
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else {
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if (a[i] == cand)
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count++;
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else
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count--;
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}
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}for (int i = 0; i < a.length; i++) {
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if (a[i] == cand)
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count++;}
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if (count > (a.length / 2))
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return cand;
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return -1;
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}
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public static void main(String args[]){
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Scanner input=new Scanner(System.in);
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int n=input.nextInt();
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int a[]=new int[n];
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for(int i=0;i<n;i++){
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a[i]=input.nextInt();
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}
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System.out.println("the majority element is "+findmajor(a));
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}
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}
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