diff --git a/cpp/24game.cpp b/cpp/24game.cpp
index 0da81d7..a288125 100644
--- a/cpp/24game.cpp
+++ b/cpp/24game.cpp
@@ -1,17 +1,176 @@
+// Reference code: https://www.jb51.net/article/182079.htm
 #include <iostream>
 #include <string>
 #include <ctime>
+#include <vector>
 
-//生成在[begin,end]范围内的随机数
-double randnum(int begin = 0, int end = 1){
-    srand(time(NULL));
-    return (rand()%(end-begin+1))+begin;
+typedef std::string string;
+
+// Generate a number in [begin,end]
+static double randnum(int begin = 0, int end = 1)
+{
+    return rand() % (end - begin + 1) + begin;
 }
 
-//24点主类
-class Game24{};
+// The Game Class
+class Game24
+{
+public:
+    Game24() {}
 
-int main(int argc, char ** argv){
-    printf("%f",randnum(1,13));
+    void startgame()
+    {
+        bool winned = false;
+        string user_result;
+        getnumbers();
+        std::cin >> user_result;
+
+        // Format result number
+        if(user_result[user_result.length()] != ')' || user_result[0] != '('){
+            user_result = '(' + user_result + ')';
+        }
+
+        // Check user input and the results
+        for (std::vector<string>::iterator it = result_strings.begin(); it != result_strings.end(); it++)
+        {
+            if (*it == user_result)
+            {
+                std::cout << "Winned!" << std::endl;
+                winned = true;
+                break;
+            }
+            else
+            {
+                continue;
+            }
+        }
+
+        // If lost, output information
+        if(!winned){
+            std::cout<<"Lost"<<std::endl;
+        }
+    }
+
+    void getnumbers()
+    {
+        srand(time(NULL));
+        for (int i = 0; i < n; i++)
+        {
+            // Get Number and output
+            number[i] = randnum(1, 13);
+            std::cout << number[i] << " ";
+
+            // Process number to string for display
+            switch ((int)number[i])
+            {
+            case 10:
+                result[i] = "10";
+                break;
+            case 11:
+                result[i] = "11";
+                break;
+            case 12:
+                result[i] = "12";
+                break;
+            case 13:
+                result[i] = "13";
+                break;
+            default:
+                result[i] = '0' + number[i];
+            }
+        }
+        std::cout << std::endl;
+
+        // Get the algorithm that can get the result
+        F(n);
+        std::cout << "Has" << count << "Results" << std::endl;
+    }
+
+private:
+    int n = 4;                           // Flag of third calculate
+    double number[4] = {0};              // Numbers
+    char oper[4] = {'+', '-', '*', '/'}; // operators
+    string result[4];
+    int count = 0;
+
+    std::vector<std::string> result_strings;
+
+    void F(int n)
+    {
+        // Calculate for three times
+        if (n == 1)
+        {
+            if (number[0] == 24)
+            {
+                //std::cout << result[0] << std::endl;
+                result_strings.push_back(result[0]);
+                count++;
+            }
+        }
+
+        for (int i = 0; i < n; i++)
+        {
+            for (int j = i + 1; j < n; j++)
+            {
+                double a, b;
+                string x, y;
+
+                // Save number
+                a = number[i];
+                b = number[j];
+                number[j] = number[n - 1];
+
+                // Save Result String
+                x = result[i];
+                y = result[j];
+                result[j] = result[n - 1];
+
+                // Add
+                number[i] = a + b;
+                result[i] = '(' + x + '+' + y + ')';
+                F(n - 1);
+
+                // Minus
+                number[i] = a - b;
+                result[i] = '(' + x + '-' + y + ')';
+                F(n - 1);
+                number[i] = b - a;
+                result[i] = '(' + y + '-' + x + ')';
+                F(n - 1);
+
+                // multiply
+                number[i] = a * b;
+                result[i] = '(' + x + '*' + y + ')';
+                F(n - 1);
+
+                // divide
+                if (b != 0)
+                {
+                    number[i] = a / b;
+                    result[i] = '(' + x + '/' + y + ')';
+                    F(n - 1);
+                }
+
+                if (a != 0)
+                {
+                    number[i] = b / a;
+                    result[i] = '(' + y + '/' + x + ')';
+                    F(n - 1);
+                }
+
+                // if the result is not 24, make the numbers back
+                number[i] = a;
+                number[j] = b;
+                result[i] = x;
+                result[j] = y;
+            }
+        }
+    }
+};
+
+int main(int argc, char **argv)
+{
+    Game24 game1;
+    game1.startgame();
     return 0;
-}
\ No newline at end of file
+}