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diff --git a/challenge-242/paulo-custodio/cpp/ch-2.cpp b/challenge-242/paulo-custodio/cpp/ch-2.cpp
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+/*
+Challenge 242
+
+Task 2: Flip Matrix
+Submitted by: Mohammad S Anwar
+You are given n x n binary matrix.
+
+Write a script to flip the given matrix as below.
+
+
+1 1 0
+0 1 1
+0 0 1
+
+a) Reverse each row
+
+0 1 1
+1 1 0
+1 0 0
+
+b) Invert each member
+
+1 0 0
+0 0 1
+0 1 1
+
+Example 1
+Input: @matrix = ([1, 1, 0], [1, 0, 1], [0, 0, 0])
+Output: ([1, 0, 0], [0, 1, 0], [1, 1, 1])
+Example 2
+Input: @matrix = ([1, 1, 0, 0], [1, 0, 0, 1], [0, 1, 1, 1], [1, 0, 1, 0])
+Output: ([1, 1, 0, 0], [0, 1, 1, 0], [0, 0, 0, 1], [1, 0, 1, 0])
+*/
+
+#include <algorithm>
+#include <iostream>
+#include <regex>
+#include <string>
+#include <vector>
+using namespace std;
+
+vector<string> regex_split(const string& s, const regex& sep_regex = regex{ "\\s+" }) {
+    sregex_token_iterator iter(s.begin(), s.end(), sep_regex, -1);
+    sregex_token_iterator end;
+    return { iter, end };
+}
+
+vector<int> parse_list(const string& text) {
+    vector<int> result;
+    auto nums = regex_split(text, regex{ "[\\[\\](),; \\t]+" });
+    for (auto& num : nums) {
+        if (!num.empty()) {
+            int n = stoi(num);
+            result.push_back(n);
+        }
+    }
+    return result;
+}
+
+
+vector<vector<int>> parse_matrix(const string& text) {
+    vector<vector<int>> matrix;
+    auto rows_text = regex_split(text, regex("\\],"));
+    for (auto& row_text : rows_text) {
+        auto row = parse_list(row_text);
+        matrix.push_back(row);
+    }
+    return matrix;
+}
+
+void process_matrix(vector<vector<int>>& matrix) {
+    for (auto& row : matrix) {
+        // a) Reverse each row
+        reverse(row.begin(), row.end());
+
+        // b) Invert each member
+        for (auto& n : row)
+            n = 1 - n;
+    }
+}
+
+void print_list(const vector<int>& arr) {
+    cout << "[";
+    string sep = "";
+    for (auto& n : arr) {
+        cout << sep << n;
+        sep = ", ";
+    }
+    cout << "]";
+}
+
+void print_matrix(vector<vector<int>>& matrix) {
+    cout << "(";
+    string sep = "";
+    for (auto& row : matrix) {
+        cout << sep;
+        print_list(row);
+        sep = ", ";
+    }
+    cout << ")";
+}
+
+int main(int argc, char* argv[]) {
+    if (argc != 2) {
+        cerr << "Usage: ch-2 '([a, b, c], [d, e, f], [g, h, i])'" << endl;
+        exit(EXIT_FAILURE);
+    }
+
+    auto matrix = parse_matrix(argv[1]);
+    process_matrix(matrix);
+    print_matrix(matrix);
+#if 0
+    free_matrix(matrix);
+
+    utarray_free(matrix);
+#endif
+}
+#if 0
+
+
+void free_matrix(UT_array* matrix) {
+    for (UT_array** p = NULL; (p = utarray_next(matrix, p)) != NULL; ) {
+        utarray_free(*p);
+        *p = NULL;
+    }
+}
+
+#endif