Cod sursa(job #2432946)

Utilizator AndreiStanescuAlloys Nokito AndreiStanescu Data 25 iunie 2019 15:50:35
Problema Potrivirea sirurilor Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
//pattern matching
//KMP-in O(n+m)
#include<iostream>
#include<cstring>
#include<fstream>
#define N 2000000
using namespace std;

char P[N],T[N];
int m,n,poz[N],st[1001];

void citire()
{
    ifstream fin("strmatch.in");
    fin.getline(P+1,N);
    fin.getline(T+1,N);
    P[0]=' ';
    T[0]=' ';
    m=strlen(P)-1;
    n=strlen(T)-1;
    fin.close();

}


void constr()
{
    poz[1]=0;
    int k=0;
    for(int q=2;q<=m;q++)
    {
        while(k>0 && P[k+1]!=P[q])
            k=poz[k];
        if(P[k+1]==P[q]) k++;
        poz[q]=k;
    }

}

void KMP()
{
    int q=0,i,ans=0;
    for(i=1;i<=n;i++)
    {
        while(q && P[q+1]!=T[i])
            q=poz[q];
        if(P[q+1]==T[i]) q++;
        if(q==m)
           {
               //cout<<i-m<<' ';
               ans++;
               st[ans]=i-m;
           //q=poz[q];
           }

    }
    ofstream fout("strmatch.out");
    fout<<ans<<endl;
    for(i=1;i<=min(1000,ans);i++)
        fout<<st[i]<<' ';
    fout.close();


}



int main()
{
    citire();
    constr();
    //for(int i=1;i<=m;i++) cout<<poz[i]<<' ';
    KMP();
}