Cod sursa(job #1904238)

Utilizator ajeccAjechiloae Eugen ajecc Data 5 martie 2017 13:55:38
Problema Ciclu hamiltonian de cost minim Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 3.76 kb
#include <bits/stdc++.h>
#define for0(i,n) for(int i=0; i<n; i++)
#define for1(i,n) for(int i=1; i<=n; i++)
#define pb push_back
#define mp make_pair
#define all(v) v.begin(), v.end()
#define V vector<int>
#define VP vector<pair<int, int> >
#define clr(A,x) memset(A, x, sizeof(A))
#define cpy(A,B) memcpy(A, B, sizeof(B))
#define g(stream, s) getline(stream, s)
#define FASTIO ios_base::sync_with_stdio(0)
typedef long long ll;
typedef unsigned long long ull;
using namespace std;

const int CHARMAX = (1 << 10);
const int INFINT = 2000000000;
const ll INFLL = (1LL << 62);

/*class InParsare
{
private:
    FILE *fin;
    char *buffer;
    size_t index_of_buffer;

    char read_character()
    {
        index_of_buffer++;
        if(index_of_buffer == CHARMAX)
        {
            fread(buffer, 1, CHARMAX, fin);
            index_of_buffer = 0;
        }
        return buffer[index_of_buffer];
    }

public:
    InParsare(const char *name)
    {
        fin = fopen(name, "r");
        buffer = new char[CHARMAX]();
        index_of_buffer = CHARMAX - 1;
    }

    template<class T>
    InParsare &operator >> (T &n)
    {
        char c;
        while(!isdigit(c = read_character()) && c != '-');

        int sgn = 1;
        if(c == '-')
        {
            n = 0;
            sgn = -1;
        }
        else n = c - '0';

        while(isdigit(c = read_character()))
            n = n * 10 + c - '0';
        n *= sgn;

        return *this;
    }
};

class OutParsare
{
private:
    FILE *fout;
    char *buffer;
    size_t index_of_buffer;

    void write_character(char character)
    {
        if(index_of_buffer == CHARMAX)
        {
            fwrite(buffer, 1, CHARMAX, fout);
            index_of_buffer = 0;
            buffer[index_of_buffer++] = character;
        }
        else buffer[index_of_buffer++] = character;
    }

public:

    OutParsare(const char *name)
    {
        fout = fopen(name, "w");
        buffer = new char[CHARMAX]();
        index_of_buffer = 0;
    }

    ~OutParsare()
    {
        fwrite(buffer, 1, index_of_buffer, fout);
        fclose(fout);
    }
    template<class T>
    OutParsare &operator << (T n)
    {
        if(typeid(T).name() == typeid(char).name())
        {
            write_character(n);
            return *this;
        }

        if(n <= 9)
            write_character(n + '0');
        else
        {
            (*this) << (n / 10);
            write_character(n % 10 + '0');
        }

        return *this;
    }

};*/

//InParsare fin("statiuni.in"); /// merg numai pt numere
//OutParsare fout("statiuni.out"); /// merg numai pt numere + caractere individuale, nu stringuri
ifstream fin("hamilton.in");
ofstream fout("hamilton.out");

const int NMAX = 19;
const int MOD = 666013;

int n, m;
V graf[NMAX];
int dp[NMAX][(1 << 18) + 1], cost[NMAX][NMAX];
int sol = INFINT;

int calc(int nod, int putere)
{
    if(dp[nod][putere] != -1)
        return dp[nod][putere];

    dp[nod][putere] = INFINT;
    for(auto it: graf[nod])
        if((putere & (1 << it)) && it != 0)
            dp[nod][putere] = min(dp[nod][putere], calc(it, putere ^ (1 << nod)) + cost[it][nod]);

    return dp[nod][putere];
}


int main()
{
    int n, m;
    fin >> n >> m;

    for0(i, n)
        for0(j, n)
            cost[i][j] = INFINT;

    for0(i, m)
    {
        int a, b, c;
        fin >> a >> b >> c;
        graf[b].pb(a);
        cost[a][b] = c;
    }

    memset(dp, -1, sizeof(dp));
    dp[0][1] = 0;

    for(auto it: graf[0])
        sol = min(sol, calc(it, (1 << n) - 1) + cost[it][0]);

    if(sol == INFINT) return fout << "Nu exista solutie\n", 0;
    fout << sol << '\n';
    return 0;
}