Merge pull request #61 from PawanJaiswal0843/master

1823.find-the-winner-of-the-circular-game.cpp

Author: PawanJaiswal08

1823.find-the-winner-of-the-circular-game.cpp

@@ -0,0 +1,49 @@
+// 1823. Find the Winner of the Circular Game
+// Josephus Problem
+#include<bits/stdc++.h>
+using namespace std;
+
+void solve(vector<int> &arr, int index, int k){
+    if(arr.size() == 1)
+        return;
+
+    index = (index + k) % arr.size();
+    
+    arr.erase(arr.begin() + index);
+    index--;
+    
+    solve(arr, index, k);
+}
+
+int findTheWinner(int n, int k) {
+    vector<int> arr;
+    for(int i = 1; i <= n; i++){
+        arr.push_back(i);
+    }
+    int index = -1;
+    solve(arr, index, k);
+    return arr[0];
+}
+
+int main(){
+    // Input: n = 5, k = 2
+    // Output: 3
+    // Explanation: Here are the steps of the game:
+    // 1) Start at friend 1.
+    // 2) Count 2 friends clockwise, which are friends 1 and 2.
+    // 3) Friend 2 leaves the circle. Next start is friend 3.
+    // 4) Count 2 friends clockwise, which are friends 3 and 4.
+    // 5) Friend 4 leaves the circle. Next start is friend 5.
+    // 6) Count 2 friends clockwise, which are friends 5 and 1.
+    // 7) Friend 1 leaves the circle. Next start is friend 3.
+    // 8) Count 2 friends clockwise, which are friends 3 and 5.
+    // 9) Friend 5 leaves the circle. Only friend 3 is left, so they are the winner.
+    int n = 4, k = 2;
+    cout << findTheWinner(n,k);
+    return 0;
+}
+
+// for(int i = 0; i < arr.size(); i++){
+//     cout << arr[i] << ' ';
+// }
+// cout<<endl;