C++ Simboliai

//Petras Petraitis 39212121234
#include <iostream>
#include <fstream>
#include <string>

using namespace std;

struct Duom {
    string vard;
    string pav;
    long long int kodas;
};

void Nuskaitymas(Duom A[], int & n);

void Ieskoti(Duom A[], Duom B[], int n, int & m, int men);

void Irasymas(Duom B[], int m);

int metai[100], meen[100], diena[100];

int main(){

    Duom A[100];
    Duom B[100];

    int men;
    int n, m = 0;

    cout << "Nurodykite menesi :" << endl;
    cin >> men;

    Nuskaitymas(A, n);

    Ieskoti(A, B, n, m, men);

    Irasymas(B, m);

    return 0;
}

void Nuskaitymas(Duom A[], int & n){
    ifstream FD("Duomenys.txt");
        FD >> n;
        for(int i = 0; i < n; i++){
            FD >> A[i].vard >> A[i].pav >> A[i].kodas;
        }
    FD.close();
}

void Ieskoti(Duom A[], Duom B[], int n, int & m, int men){
    int vyr, menesis = 0, j = 0;
    for(int i = 0; i < n; i++){
        vyr = A[i].kodas / 10000000000;
        if(vyr == 3){
            menesis = A[i].kodas / 1000000;
            menesis = menesis % 100;
            //meen = menesis;
            if(men == menesis){
                    B[m].vard = A[i].vard;
                    B[m].pav = A[i].pav;
                    B[m].kodas = A[i].kodas;

                    metai[m] = A[i].kodas / 100000000;
                    metai[m] = metai[m] % 100;
                    meen[m] = A[i].kodas / 1000000;
                    meen[m] = meen[m] % 100;
                    diena[m] = A[i].kodas / 10000;
                    diena[m] = diena[m] % 100;
                    m++;
            } // men
        } // vyr
    } // for
}

void Irasymas(Duom B[], int m){
    ofstream FR("Rezultatai.txt");
    if(m > 0){
        for(int i = 0; i < m; i++){
            FR << B[i].vard << " " << B[i].pav << " " << "19" << metai[i] << "." << meen[i] << "." << diena[i] << endl;
        }
    } else {
        FR << "Nera tokiu mokiniu su nurodytu menesiu";
    }
    FR.close();
}