Boyer Moore’s Voting Algorithm in C++

C-Plus-Plus/Algorithms/Boyer_Moore_Majority_Vote.cpp

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+// C++ Program for finding out 
+// Majority Element in an array  
+#include <bits/stdc++.h> 
+using namespace std; 
+
+/* Function to find the candidate with the Majority */
+int findCandidate(int a[], int size) 
+{ 
+    int majority_element = 0, count = 1; 
+    for (int i = 1; i < size; i++) { 
+        if (a[majority_element] == a[i]) 
+            count++; 
+        else
+            count--; 
+        if (count == 0) { 
+            majority_element = i; 
+            count = 1; 
+        } 
+    } 
+    return a[majority_element]; 
+} 
+
+/* Function to check if the candidate 
+   occurs more than n/2 times */
+bool isMajority(int a[], int size, int cand) 
+{ 
+    int count = 0; 
+    for (int i = 0; i < size; i++) 
+
+        if (a[i] == cand) 
+            count++; 
+
+    if (count > size / 2) 
+        return 1; 
+
+    else
+        return 0; 
+} 
+
+/* Function to print the Majority Element */
+void printMajority(int a[], int size) 
+{ 
+    /* Find the candidate for Majority*/
+    int cand = findCandidate(a, size); 
+
+    /* Print the candidate if it is Majority*/
+    if (isMajority(a, size, cand)) 
+        cout << " " << cand << " "; 
+
+    else
+        cout << "No Majority Element"; 
+} 
+
+/* Driver code */
+/* int main() 
+{ 
+    int a[] = { 1, 3, 3, 1, 2 }; 
+    int size = (sizeof(a)) / sizeof(a[0]); 
+
+    // Function calling 
+    printMajority(a, size); 
+
+    return 0; 
+}
+
+Output - No Majority Element */
+
+/* Time Complexity: O(n). The time complexity is linear.
+Auxiliary Space: O(1).  No extra space is required */
+