#include"3.22.h" int menu() { int c; cout << "0-9以内的多项式计算" << endl; cout << "1.计算" << endl; cout << "0.退出\n" << endl; cout << "选择:"; cin >> c; return c; } void main() { while (1) { switch (menu()) { case 1: { cout << "请输入要计算的表达式(操作数和结果都在0-9的范围内,以#结束):" << endl; char res = EvaluateExpression();//算法3.22 表达式求值 cout << "计算结果为" << res - 48 << endl << endl; } break; case 0: cout << "退出成功\n" << endl; exit(0); default: break; } } }