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#include <iostream>
#include <string>
#include <vector>
#include <cassert>
enum class Op
{
Add,
Sub,
Mul,
Div
};
struct OpInfo
{
explicit OpInfo(Op op) : op(op), count(0) {}
Op op;
int count; // operand count
};
int main()
{
std::string expr;
std::getline(std::cin, expr);
std::vector<int> operands;
std::vector<OpInfo> op_infos;
for (auto c : expr)
{
if (c == '+')
{
op_infos.emplace_back(Op::Add);
}
else if (c == '-')
{
op_infos.emplace_back(Op::Sub);
}
else if (c == '*')
{
op_infos.emplace_back(Op::Mul);
}
else if (c == '/')
{
op_infos.emplace_back(Op::Div);
}
else if (c == '(')
{
if (!op_infos.empty())
op_infos.back().count++;
}
else if (c >= '0' && c <= '9')
{
operands.push_back(c - '0');
op_infos.back().count++;
}
else if (c == ')')
{
const auto &info = op_infos.back();
if ((info.op == Op::Sub || info.op == Op::Div) && info.count != 2)
{
std::cerr << "Sub or Div Op has not 2 operands.";
return 1;
}
switch (info.op)
{
case Op::Add:
{
int r = 0;
for (int i = 0; i < info.count; i++)
{
r += operands.back();
operands.pop_back();
}
operands.push_back(r);
op_infos.pop_back();
break;
}
case Op::Sub:
{
int a = operands.back();
operands.pop_back();
int b = operands.back();
operands.pop_back();
operands.push_back(b - a);
op_infos.pop_back();
break;
}
case Op::Mul:
{
int r = 1;
for (int i = 0; i < info.count; i++)
{
r *= operands.back();
operands.pop_back();
}
operands.push_back(r);
op_infos.pop_back();
break;
}
case Op::Div:
{
int a = operands.back();
operands.pop_back();
int b = operands.back();
operands.pop_back();
operands.push_back(b / a);
op_infos.pop_back();
break;
}
default:
std::terminate();
}
}
}
if (operands.size() != 1)
{
std::cerr << "final operand count is not 1, but " << operands.size();
return 1;
}
if (!op_infos.empty())
{
std::cerr << "final op_info is not empty";
return 1;
}
std::cout << operands.front();
return 0;
}
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