逆波兰式动画演示代码

#include <iostream>
#include <stack>
#include <string>
using namespace std;

bool isOperator(char c) {
    return (c == '+' || c == '-' || c == '*' || c == '/');
}

int performOperation(char operation, int operand1, int operand2) {
    if (operation == '+') {
        return operand1 + operand2;
    } else if (operation == '-') {
        return operand1 - operand2;
    } else if (operation == '*') {
        return operand1 * operand2;
    } else if (operation == '/') {
        return operand1 / operand2;
    }
    return -1;
}

int evaluatePostfix(string exp) {
    stack<int> s;
    for (char& c : exp) {
        if (isdigit(c)) {
            s.push(c - '0');
        } else if (isOperator(c)) {
            int operand2 = s.top();
            s.pop();
            int operand1 = s.top();
            s.pop();
            int result = performOperation(c, operand1, operand2);
            s.push(result);
        }
    }
    return s.top();
}

int main() {
    string exp = "231*+9-";
    cout << "The result of evaluation is: " << evaluatePostfix(exp);
    return 0;
}