Cod sursa(job #2477258)

Utilizator PetrescuAlexandru Petrescu Petrescu Data 19 octombrie 2019 21:42:13
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.75 kb
#include <iostream>
#include <vector>
#define MAX 100000

using namespace std;

struct solComp
{
    int num;
    char c;
};

int solve(string s)
{
    vector<solComp> sol;
    vector<int> stiva;

    int n = s.length(), m, i;

    for(i = 0; i < n; i++)
    {
        if(s[i] == '(')stiva.push_back(s[i]);
        else if(s[i] == '*' || s[i] == '/')
        {
            m = stiva.size() - 1;
            while(m >= 0 && (stiva[m] == '*' || stiva[m] == '/') && stiva[m] != '(')
            {
                solComp aux;

                aux.num = -1;
                aux.c = stiva[m];

                sol.push_back(aux);
                stiva.pop_back();
                m--;
            }

            stiva.push_back(s[i]);
        }
        else if(s[i] == '+' || s[i] == '-')
        {
            m = stiva.size() - 1;
            while(m >= 0 && stiva[m] != '(')
            {
                solComp aux;

                aux.num = -1;
                aux.c = stiva[m];

                sol.push_back(aux);
                stiva.pop_back();
                m--;
            }

            stiva.push_back(s[i]);
        }
        else if(s[i] == ')')
        {
            m = stiva.size() - 1;
            while(stiva[m] != '(')
            {
                solComp aux;

                aux.num = -1;
                aux.c = stiva[m];

                sol.push_back(aux);
                stiva.pop_back();
                m--;
            }
            stiva.pop_back();
        }
        else
        {
            int number = s[i] - '0';

            for(i = i + 1; i < n && '0' <= s[i] && s[i] <= '9'; i++)number = number * 10 + s[i] - '0';

            i--;
            solComp aux;

            aux.num = number;
            aux.c = 0;

            sol.push_back(aux);
        }
    }

    m = stiva.size() - 1;

    while(m >= 0)
    {
        solComp aux;

        aux.num = -1;
        aux.c = stiva[m];

        sol.push_back(aux);
        stiva.pop_back();

        m--;
    }

    n = sol.size();

    for(i = 0; i < n; i++)
        if(sol[i].num == -1)
        {
            if(sol[i].c == '/')stiva[m - 1] = stiva[m - 1] / stiva[m];
            else if(sol[i].c == '*')stiva[m - 1] = stiva[m - 1] * stiva[m];
            else if(sol[i].c == '+')stiva[m - 1] = stiva[m - 1] + stiva[m];
            else stiva[m - 1] = stiva[m - 1] - stiva[m];

            m--;

        }
        else
        {
            m++;
            stiva[m] = sol[i].num;
        }

    return stiva[0];
}

int main()
{
    string s;

    freopen("evaluare.in", "r", stdin);
    freopen("evaluare.out", "w", stdout);

    cin >> s;

    cout << solve(s);

    return 0;
}