c++数据结构堆栈加减乘除运算器 我从教科书上copy了一段代码但是输入后直接停止工作求解

Question

我输入的是自带测试用例运算式
（（（60+40）/50*（16-4））
#include
#include
#include
#include
#include
using namespace std;
double read_and_evaluate(istream& ins);
void evaluate_stack_tops(stack& numbers,stack& operations);
int main()
{
double answer;
cout<<"Type a fully parenthesized arithmetic expression:"< answer= read_and_evaluate(cin);
cout return EXIT_SUCCESS;
}
double read_and_evaluate(istream& ins)
{
const char DECIMAL = '.';
const char RIGHT_PARENTHESIS = ')';
stack numbers;
stack operations;
double number;
char symbol;
while(ins&&ins.peek() != '\n')
{
if(isdigit(ins.peek())||(ins.peek()==DECIMAL))
{
ins>>number;
numbers.push(number);
}
else if(strchr("+-*/",ins.peek())!=NULL)
{
ins>>symbol;
operations.push(number);
}
else if(ins.peek()==RIGHT_PARENTHESIS)
{
ins.ignore();
evaluate_stack_tops(numbers,operations);
}
else
ins.ignore();
}
return numbers.top();
}
void evaluate_stack_tops(stack& numbers, stack& operations)
{
double operand1,operand2;
operand2=numbers.top();
numbers.pop();
operand1=numbers.top();
numbers.pop();
switch(operations.top())
{
case '+': numbers.push(operand1+operand2);
break;
case '-': numbers.push(operand1-operand2);
break;
case '*': numbers.push(operand1*operand2);
break;
case '/': numbers.push(operand1/operand2);
break;
}
operations.pop();
}

Answer 1

设置断点单步调试一下。应该是某个地方指针操作不正确。