Cod sursa(job #1183247)

Utilizator MarianMMorosac George Marian MarianM Data 8 mai 2014 18:00:01
Problema Potrivirea sirurilor Scor 18
Compilator cpp Status done
Runda Arhiva educationala Marime 1.47 kb
#include <fstream>
#include <cstdio>
#include <string>
#include <vector>
#include <list>
using namespace std;

ifstream fin("strmatch.in");
ofstream fout("strmatch.out");

#define DMAX 2000001

#define PRIME1 7
#define PRIME2 13

#define D 123

string P, T;
int hashP1, hashT1, h1 = 1;
int hashP2, hashT2, h2 = 1;
int s[1002];	int nos;

int main(){
	int i, lgP, lgT, shift; char x;

	fin >> P; lgP = P.size();
	for (i = 0; i < lgP; i++) // 2*O(DMAX)
		hashP1 = (D * hashP1 + P[i]) % PRIME1,
		hashP2 = (D * hashP2 + P[i]) % PRIME2;
	
	fin.get(x); 
	fin >> T; lgT = T.size();
	if (lgP > lgT) { fout << "0 \n"; return 0; }
	if (P == T) { fout << "1\n" << "0 \n"; return 0; }
	for (i = 0; i < lgP; i++){ // 2*O(DMAX)
		hashT1 = (D * hashT1 + T[i]) % PRIME1,
		hashT2 = (D * hashT2 + T[i]) % PRIME2;
	}
	
	for (i = 1; i < lgP; i++) // 2*O(DMAX)
		h1 = (h1 * D) % PRIME1,
		h2 = (h2 * D) % PRIME2;
	
	shift = 0;
	while (shift <= lgT - lgP){ // O(DMAX/2) * 
		if (hashP1 == hashT1 && hashP2 == hashT2){
				//for (i = 0; i < lgP; i++)	if (P[i] != T[i + shift])	break; // O(m)
				//if (i == lgP){
					nos++;
					if (nos <= 1000) s[nos] = shift;
				//}
			}

		hashT1 = ((hashT1 - (T[shift] * h1) % PRIME1 + PRIME1)*D + T[shift + lgP]) % PRIME1;
		hashT2 = ((hashT2 - (T[shift] * h2) % PRIME2 + PRIME2)*D + T[shift + lgP]) % PRIME2;
		shift++;
	}

	fout << nos << '\n';
	for (i = 0; i < nos && i < 1000; i++) 
		fout << s[i+1] << ' ';

	return 0;
}