T12

#include<iostream>
#include<fstream>
#include<vector>
#include<thread>
#include<mutex>
typedef unsigned char BYTE;

using namespace std;
mutex m;
void XOR(int begin, int end, vector<BYTE> in, vector<BYTE> key, vector<BYTE> &rez){
    for(int i= begin; i< end; i ++){
        int k = i % 256;
        BYTE tmp;
        tmp = in[i] ^ key[k];
        //rez.emplace(rez.end(), tmp);
        //rez.push_back(tmp);
        rez[i] = tmp;
        //cout<< i ;
    }

}

vector<BYTE> fileToVector(string filename){
    int size;
    ifstream file;
    file.open(filename, ios::in|ios::binary);
    file.read((char*)&size, 4);
    file.seekg(4, ios::beg);
    vector<BYTE> v(size);
    file.read((char*)&v[0],size);
    return v;
}



int main(){
    int thread_num = 22 ;
    vector<BYTE> in = fileToVector("in.dat");
    vector<BYTE> key = fileToVector("key.dat");
    vector<BYTE> out(in.size());
    thread t[thread_num];

    int split = in.size()/thread_num;

    for(int i=0; i<thread_num - 1; i++){
        t[i] = thread(XOR, i*split, (i+1)*split, in, key, ref(out));
    }

    //nit koja kupi ostatak kad broj niti nije stepen dvojke
    t[thread_num - 1] = thread(XOR, (thread_num - 1)*split,in.size(), in, key, ref(out));

    for(int i=0; i<thread_num; i++){
        t[i].join();
    }

    ofstream f;
    f.open("test.dat", ios::binary);
    int vel = out.size();
    f.write((char*)&vel, sizeof(vel));

    for(BYTE i:out)
        f<<i;



    return 0;
}