#include <bits/stdc++.h>
#include "biginteger.h"

using namespace std;

BigInteger::BigInteger(string x) {
    number = x;
}

BigInteger::~BigInteger() {

}

void BigInteger::add(BigInteger y) {
    string aux;
    int s = 0;
    reverse(this->number.begin(),this->number.end());
    reverse(y.number.begin(),y.number.end());
    int i;
    bool flag = false;
    if(this->number.size() < y.number.size()) {
        swap(this->number,y.number);
        flag = true;
    }
    for(i = 0;i < this->number.size();i++) {
        int a = this->number[i] - '0' + y.number[i] - '0' + s;
        s = a/10;
        a %= 10;
        aux.push_back(a+'0');
        if(i == y.number.size()-1)
            break;
    }
    i++;
    for(;i < this->number.size();i++) {
        int a = this->number[i] - '0' + s;
        s = a/10;
        a %= 10;
        aux.push_back(a+'0');
    }
    if(s == 1)
        aux.push_back(1);

    if(flag)
        swap(this->number,y.number);

    reverse(aux.begin(),aux.end());
    reverse(y.number.begin(),y.number.end());
    this->number = aux;
}

void BigInteger::less(BigInteger y) {
    string aux;
    string z = y.number;
    int s = 0;
    bool flag = false;
    if(this->number < z) {
        //cout << "Entrou aqui" << endl;
        swap(this->number,z);
        flag = true;
    }
    reverse(this->number.begin(),this->number.end());
    reverse(z.begin(),z.end());
    int i;
    for(i = 0;i < this->number.size();i++) {
        int a = this->number[i] - '0' - (z[i] - '0') + s;
        if(a < 0) {
            a += 10;
            s = -1;
        }
        else
            s = 0;
        aux.push_back(a+'0');
        if(i == z.size()-1)
            break;
    }
    i++;
    for(;i<this->number.size();i++) {
        int a = this->number[i] - '0' + s;
        if(a < 0) {
            a += 10;
            s = -1;
        }
        else
            s = 0;
        aux.push_back(a+'0');
    }
    while(!aux.empty() && aux[aux.size()-1] == '0') {
        aux.erase(aux.end()-1,aux.end());
    }
    if(aux.size() == 0)
        aux.push_back('0');
    if(flag)
        aux.push_back('-');
    reverse(aux.begin(),aux.end());
    this->number = aux;
}

void BigInteger::print() {
    cout << this->number << endl;
}