Cod sursa(job #2801494)

Utilizator AndreidreiGresoiu Liviu-Andrei Andreidrei Data 16 noiembrie 2021 13:01:12
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 3.64 kb
#include <bits/stdc++.h>
#define din cin
#define dout out
#define pi 3.14159265359
#define sw(x,y) x^=y,y^=x,x^=y
#define bmin(a,b)(((a)<(b))?(a):(b))
#define bmax(a,b)((a>b)?(a):(b))
#define ll long long
#define forq(i,ii,n)for(i=ii;i<n;i++)
using namespace std;
//ifstream in("rf.in");
ofstream out("bellmanford.out");
class OutParser
{
private:
    FILE *fout;
    char *buff;
    int sp;

    void write_ch(char ch)
    {
        if (sp == 50000)
        {
            fwrite(buff, 1, 50000, fout);
            sp = 0;
            buff[sp++] = ch;
        }
        else
        {
            buff[sp++] = ch;
        }
    }

public:
    OutParser(const char *name)
    {
        fout = fopen(name, "w");
        buff = new char[50000]();
        sp = 0;
    }
    ~OutParser()
    {
        fwrite(buff, 1, sp, fout);
        fclose(fout);
    }

    OutParser &operator<<(int vu32)
    {
        if (vu32 <= 9)
        {
            write_ch(vu32 + '0');
        }
        else
        {
            (*this) << (vu32 / 10);
            write_ch(vu32 % 10 + '0');
        }
        return *this;
    }

    OutParser &operator<<(long long vu64)
    {
        if (vu64 <= 9)
        {
            write_ch(vu64 + '0');
        }
        else
        {
            (*this) << (vu64 / 10);
            write_ch(vu64 % 10 + '0');
        }
        return *this;
    }

    OutParser &operator<<(char ch)
    {
        write_ch(ch);
        return *this;
    }
    OutParser &operator<<(const char *ch)
    {
        while (*ch)
        {
            write_ch(*ch);
            ++ch;
        }
        return *this;
    }
};
class InParser
{
private:
    FILE *fin;
    char *buff;
    int sp;

    char read_ch()
    {
        ++sp;
        if (sp == 4096)
        {
            sp = 0;
            fread(buff, 1, 4096, fin);
        }
        return buff[sp];
    }

public:
    InParser(const char *nume)
    {
        fin = fopen(nume, "r");
        buff = new char[4096]();
        sp = 4095;
    }

    InParser &operator>>(int &n)
    {
        char c;
        while (!isdigit(c = read_ch()) && c != '-')
            ;
        int sgn = 1;
        if (c == '-')
        {
            n = 0;
            sgn = -1;
        }
        else
        {
            n = c - '0';
        }
        while (isdigit(c = read_ch()))
        {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }

    InParser &operator>>(long long &n)
    {
        char c;
        n = 0;
        while (!isdigit(c = read_ch()) && c != '-')
            ;
        long long sgn = 1;
        if (c == '-')
        {
            n = 0;
            sgn = -1;
        }
        else
        {
            n = c - '0';
        }
        while (isdigit(c = read_ch()))
        {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }
};
//OutParser out("bellmanford.out");
InParser in("bellmanford.in");
ll n,m,i,j,k,c[50001],p,v[50001];
vector<pair<ll,ll>>a[50001];
map<ll,bool>b;
int main()
{
fill(c,c+50001,LLONG_MAX/4);c[1]=0;
in>>n>>m;
while(m--)
    in>>i>>j>>k,a[i].push_back(make_pair(j,k));
b[1]=true;
while(!b.empty())
{
    k=b.begin()->first&65535,b.erase(b.begin());
    for(auto i=a[k].begin();i!=a[k].end();i++)
    {
        if(c[i->first]>i->second+c[k])
        {
            c[i->first]=i->second+c[k];
            if(++v[i->first]>n){out<<"Ciclu negativ!";return 0;}
            b[(c[i->first]<<16)+i->first]=1;
        }

    }
}
for(i=2;i<=n;i++)
    out<<c[i]<<' ';
}