Separate Black and White Balls Problem and sol.

Beginner Level 📁/Separate Black and White Balls/Solution.cpp

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+#include <iostream>
+#include <string>
+using namespace std;
+
+class Solution {
+public:
+    long long minimumSteps(string s) {
+        int n = s.length();
+        int ones = 0, zeros = 0;
+        long long count = 0;   
+        for (int i = n - 1; i >= 0; --i) {
+            if (s[i] == '0') {
+                // Count how many ones are after this zero         
+                zeros++;
+            } else {
+                // When encountering '1', we count it to match future '0's
+                count += zeros;
+                ones++;
+            }
+        }     
+        return count;
+    }
+};
+
+int main() {
+    Solution solution;
+    string s;
+
+    // Taking input string from user
+    cout << "Enter a binary string (consisting of 0's and 1's): ";
+    cin >> s;
+
+    // Calculating the minimum steps
+    long long result = solution.minimumSteps(s);
+
+    // Output the result
+    cout << "Minimum steps to rearrange the string: " << result << endl;
+
+    return 0;
+}

Beginner Level 📁/Separate Black and White Balls/question.md

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+### Separate Black and White Balls
+
+There are n balls on a table, each ball has a color black or white.
+You are given a 0-indexed binary string s of length n, where 1 and 0 represent black and white balls, respectively.
+In each step, you can choose two adjacent balls and swap them.
+Return the minimum number of steps to group all the black balls to the right and all the white balls to the left.
+
+## Example 1:
+
+Input: s = "101"
+Output: 1
+Explanation: We can group all the black balls to the right in the following way:
+- Swap s[0] and s[1], s = "011".
+Initially, 1s are not grouped together, requiring at least 1 step to group them to the right.
+
+## Example 2:
+
+Input: s = "100"
+Output: 2
+Explanation: We can group all the black balls to the right in the following way:
+- Swap s[0] and s[1], s = "010".
+- Swap s[1] and s[2], s = "001".
+It can be proven that the minimum number of steps needed is 2.
+
+## Example 3:
+
+Input: s = "0111"
+Output: 0
+Explanation: All the black balls are already grouped to the right.
+
+
+
+## Constraints:
+
+   - 1 <= n == s.length <= 105
+   - s[i] is either '0' or '1'.
+