precedence and operators

main.cpp

@@ -0,0 +1,61 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+template <typename T>
+class Stack {
+private:
+    vector<T> data;
+
+public:
+    bool empty() const {
+        return data.empty();
+    }
+
+    size_t size() const {
+        return data.size();
+    }
+
+    T& top() {
+        if (empty()) {
+            throw std::runtime_error("Stack is empty.");
+        }
+        return data.back();
+    }
+
+    const T& top() const {
+        if (empty()) {
+            throw std::runtime_error("Stack is empty.");
+        }
+        return data.back();
+    }
+
+    void push(const T& value) {
+        data.push_back(value);
+    }
+
+    void pop() {
+        if (empty()) {
+            throw std::runtime_error("Stack is empty.");
+        }
+        data.pop_back();
+    }
+};
+int precedence(char op) {
+    if (op == '+' || op == '-')
+        return 1;
+    if (op == '*' || op == '/')
+        return 2;
+    if (op == '^')
+        return 3;
+    return 0;
+}
+
+bool is_operator(char c) {
+    return c == '+' || c == '-' || c == '*' || c == '/' || c == '^' || c == '!' ||
+           c == 's' || c == 'c' || c == 't' || c == 'l' || c == 'q' || c == 'x';
+}
+
+int main() {
+    std::cout << "Hello, World!" << std::endl;
+    return 0;
+}