Cod sursa(job #3032115)

Utilizator Zed1YasuoAlex Birsan Zed1Yasuo Data 21 martie 2023 14:34:42
Problema Critice Scor 50
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 2.34 kb
#include <fstream>
#include <vector>
#include <queue>
///var prob proasta poate iau un 40?
///cresc val +1 la toate mc si fac iar fluxul
using namespace std;
ifstream f("critice.in");
ofstream g("critice.out");
int n,X,Y,Z,m;
const int N=1e3+5;
int d[N][N],b[N][N],flx[N][N];
vector<int>a[N];
int val,niv[N],p[N];
void bfs()
{
    for(int i=1;i<=n;i++)
        niv[i]=-1,p[i]=0;
    queue<int>q;
    q.push(1);
    niv[1]=0;
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for(auto x: a[nod])
            if(niv[x]==-1&&d[nod][x]-flx[nod][x]>0)
            {
                niv[x]=niv[nod]+1;
                if(x==n)
                    return;
                q.push(x);
            }
    }
}
int dfs(int nod,int flux)
{
    if(flux==0||nod==n)
        return flux;
    while(p[nod]<a[nod].size())
    {
        int x=a[nod][p[nod]];
        p[nod]++;
        if(niv[x]==niv[nod]+1&&d[nod][x]-flx[nod][x]>0)
        {
            int y=dfs(x,min(d[nod][x]-flx[nod][x],flux));
            if(y)
            {
                flx[nod][x]+=y;
                flx[x][nod]-=y;
                return y;
            }
        }
    }
    return 0;
}
bool flux_(int &ans)
{
    bfs();
    if(niv[n]==-1)
        return 0;
    else
    {
        int V=0;
        while(true)
        {
            int x=dfs(1,1e9);
            if(x==0)
                break;
            else
                V+=x;
        }
        if(V==0)
            return 0;
        ans+=V;
        return 1;
    }
    return 0;
}
struct re
{
    int x,y,z;
}T[N*10];
vector<int>sol;
int main()
{
    f>>n>>m;
    for(int i=1;i<=m;i++)
    {
        f>>X>>Y>>Z;
        T[i]={X,Y,Z};
        a[X].push_back(Y);
        a[Y].push_back(X);
        d[X][Y]=Z;
        d[Y][X]=Z;
    }
    while(flux_(val));
    for(int i=1;i<=m;i++)
    {
        for(int j=1;j<=m;j++)
        {
            d[T[j].x][T[j].y]=T[j].z;
            d[T[j].y][T[j].x]=T[j].z;
            flx[T[j].x][T[j].y]=0;
            flx[T[j].y][T[j].x]=0;
        }
        d[T[i].x][T[i].y]++;
        d[T[i].y][T[i].x]++;
        int val1=0;
        while(flux_(val1));
        if(val1>val)
            sol.push_back(i);
    }
    g<<sol.size()<<'\n';
    for(auto x : sol)
        g<<x<<'\n';
    return 0;
}