Celebrity Problem

Author: TonyStark-19

Stack/CelebrityProblem.cpp

@@ -0,0 +1,56 @@
+#include <iostream>
+#include <stack>
+#include <vector>
+using namespace std;
+
+int getCelebrity(vector<vector<int>> arr)
+{
+    stack<int> s;
+    int n = arr.size();
+
+    for (int i = 0; i < n; i++)
+    {
+        s.push(i); // push all index value
+    }
+
+    while (s.size() > 1)
+    {
+        int i = s.top();
+        s.pop();
+
+        int j = s.top();
+        s.pop();
+
+        if (arr[i][j] == 0)
+        {
+            s.push(i);
+        }
+        else
+        {
+            s.push(j);
+        }
+    }
+
+    int celeb = s.top();
+
+    for (int i = 0; i < n; i++)
+    {
+        if ((i != celeb) && (arr[i][celeb] == 0 || arr[celeb][i] == 1))
+        {
+            return -1; // no celebrity exits
+        }
+    }
+
+    return celeb;
+}
+
+int main()
+{
+    vector<vector<int>> arr = {{0, 1, 0}, {0, 0, 0}, {0, 1, 0}};
+
+    int ans = getCelebrity(arr);
+
+    cout << "Celebrity is : " << ans << endl;
+
+    return 0;
+}