/
Majority_Element.java
70 lines (62 loc) · 1.56 KB
/
Majority_Element.java
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// { Driver Code Starts
//Initial Template for Java
import java.util.*;
import java.io.*;
import java.lang.*;
class Geeks {
public static void main(String args[]) {
Scanner sc = new Scanner(System.in);
int t = sc.nextInt();
while (t-- > 0) {
int n = sc.nextInt();
int arr[] = new int[n];
for (int i = 0; i < n; i++)
arr[i] = sc.nextInt();
System.out.println(new Solution().majorityElement(arr, n));
}
}
}
class Solution {
static int majorityElement(int arr[], int n) {
if (n == 1)
return arr[0];
HashMap<Integer, Integer> hm = new HashMap<Integer, Integer>();
for (int i = 0; i < n; i++) {
if (hm.containsKey(arr[i])) {
int val = hm.get(arr[i]) + 1;
if (val > n / 2) {
return arr[i];
} else {
hm.put(arr[i], val);
}
} else {
hm.put(arr[i], 1);
}
}
return -1;
}
// public static int findMajority(int[] arr, int n) {
// int majority = 0, count = 1;
// for (int i = 1; i < n; i++) {
// if (arr[i] == arr[majority]) {
// count++;
// } else {
// count--;
// }
// if (count == 0) {
// count = 1;
// majority = i;
// }
// }
// return isMajority(arr, n, arr[majority]) ? arr[majority] : -1;
// }
// public static boolean isMajority(int[] arr, int n, int majority) {
// int count = 0;
// for (int i = 0; i < n; i++) {
// if (arr[i] == majority) {
// count++;
// }
// }
// return count > n / 2 ? true : false;
// }
}