Cod sursa(job #982872)

Utilizator cosmo0093Raduta Cosmin cosmo0093 Data 10 august 2013 13:40:59
Problema Potrivirea sirurilor Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.65 kb
#include <fstream>
#include <string>
#include <vector>

const long long pb = 257;
const long long MOD = 1000000007;

long long pow(long long x, long long a)
{
	if(a == 0) return 1;
	if(a == 1) return x % MOD;
	if(a % 2 == 0) return (pow((x * x) % MOD, a / 2)) % MOD;
	return (x * pow((x * x) % MOD, a / 2)) % MOD;
}

long long getHash(std::string& str, long long a, long long b)
{
	long long ret = 0;
	for(long long i = a; i < b; i++)
		ret = ret * pb + str[i], ret %= MOD;
	return ret;
}

bool comps(std::string& str, std::string& lstr, long long start)
{
	for(long long i = 0; i < str.length(); i++)
		if(str[i] != lstr[start + i]) return false;
	return true;
}

void rabin(std::string& str, std::string& lstr, std::vector<long long>& myV)
{
	long long comp = getHash(str, 0, str.length());
	long long ret = getHash(lstr, 0, str.length());
	long long power = pow(pb, str.length());
	if(ret == comp)
	{
		if(comps(str, lstr, 0)) 
			myV.push_back(0);
	}
	for(long long i = str.length(); i < lstr.length(); i++)
	{
		ret = ret * pb + lstr[i];
		ret %= MOD;
		ret -= (power * lstr[i - str.length()]) % MOD;
		if(ret < 0) ret += MOD;
		if(ret == comp)
		{
			if(comps(str, lstr, i - str.length() + 1)) 
				myV.push_back(i - str.length() + 1);
		}
		if(myV.size() == 1000) return;
	}
}

int main()
{
	std::ifstream in("strmatch.in");
	std::ofstream out("strmatch.out");
	std::string str, lstr;
	getline(in, str);
	getline(in, lstr);
	std::vector<long long> myV;
	rabin(str, lstr, myV);
	out << myV.size() << '\n';
	for(std::vector<long long>::iterator it = myV.begin(); it != myV.end(); it++)
		out << *it << ' ';
	return 0;
}