#include <iostream>

using namespace std;

bool triangleExists (double ko[][3][2], int index);

void findCollisions (int tr1i, int tr1m, int tr2i, int tr2m, double ko[][3][2], double r[6][2], int &c, bool &inf);

const int TR = 2;

int main()
{
    double ko[TR][3][2]; // Masīvs, kas saturēs dotās trijstūru koordinātas
    int ok; // Beigt vai turpināt programmu
    double r[6][2];
    int c = 0;
    bool inf = false;

    // Veicam darbību, kamēr lietotājs vēlas to turpināt
    do {
        c = 0;
        inf = false;

        for (int i = 0; i < TR; i++) {
                do {
                        for (int j = 0; j < 3; j++) {
                                cout << "Lūdzu ievadiet " << i + 1 << ". trijstūra " << j + 1 << ". virsotnes x koordinātu: ";
                                cin >> ko[i][j][0];
                                cout << "Lūdzu ievadiet " << i + 1 << ". trijstūra " << j + 1 << ". virsotnes y koordinātu: ";
                                cin >> ko[i][j][1];
                        }

                        if (!triangleExists(ko, i))
                                cout << "Šāds trijstūris neeksistē! Lūdzu ievadiet jaunas koordinātas!" << endl;
                } while (!triangleExists(ko, i));
        }

        for (int i = 0; i < TR; i++) {
                for (int j = i + 1; j < TR; j++) {
                        for (int k = 0; k < 3; k++) {
                                for (int l = 0; l < 3; l++) {
                                        findCollisions(i, k, j, l, ko, r, c, inf);
                                }
                        }
                }
        }

        if (inf == true) {
                cout << "Trijstūru kontūrām ir neierobežoti daudz kopīgi punkti (kāda mala pārklājas)!" << endl;
        } else {
                if (c > 0) {
                        for (int i = 0; i < c; i++) {
                                cout << "Trijstūru kontūras krustojas punktā (" << r[i][0] << ", " << r[i][1] << ")" << endl;
                        }
                } else {
                        cout << "Trijstūriem nav kopīgu punktu!" << endl;
                }
        }

        cout << "Turpināt (1) vai beigt (0) programmas izpildi?" << endl; // Piedāvajam lietotājam turpināt programmu
        cin >> ok;
    } while (ok == 1);

    return 0;
}

double max (double c1, double c2) {
        if (c1 > c2)
                return c1;
        else
                return c2;
}

double min (double c1, double c2) {
        if (c1 > c2)
                return c2;
        else
                return c1;
}

int nextLine(int curLine)
{
        if (curLine == 0)
                return 1;
        else if (curLine == 1)
                return 2;
        else if (curLine == 2)
                return 0;
        else
                return -1;
}

bool triangleExists(double ko[][3][2], int index)
{
        if (ko[index][0][0] == ko[index][1][0] && ko[index][1][0] == ko[index][2][0] || ko[index][0][1] == ko[index][1][1] && ko[index][1][1] == ko[index][2][1])
                return false;
        else
                return true;
}

void findCollisions (int tr1i, int tr1m, int tr2i, int tr2m, double ko[][3][2], double r[6][2], int &c, bool &inf)
{
        int tr1m2 = nextLine(tr1m), tr2m2 = nextLine(tr2m);

        if (tr1m2 == -1 || tr2m2 == -1) {
                cout << "Norādīta neeksistējoša trijstūra mala!";
        }

        double x1 = ko[tr1i][tr1m][0], x2 = ko[tr1i][tr1m2][0], x3 = ko[tr2i][tr2m][0], x4 = ko[tr2i][tr2m2][0];
        double y1 = ko[tr1i][tr1m][1], y2 = ko[tr1i][tr1m2][1], y3 = ko[tr2i][tr2m][1], y4 = ko[tr2i][tr2m2][1];
        double slope1 = (y2 - y1) / (x2 - x1);
        double slope2 = (y4 - y3) / (x4 - x3);

        if (slope1 != slope2) {
                double x = ((x1 * y2 - y1 * x2) * (x3 - x4) - (x1 - x2) * (x3 * y4 - y3 * x4))/((x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4));
                double y = ((x1 * y2 - y1 * x2) * (y3 - y4) - (y1 - y2) * (x3 * y4 - y3 * x4))/((x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4));

                if (min(x1, x2) <= x && x <= max(x1, x2) &&
                    min(y1, y2) <= y && y <= max(y1, y2) &&
                    min(x3, x4) <= x && x <= max(x3, x4) &&
                    min(y3, y4) <= y && y <= max(y3, y4)){
                        if (c > 0) {
                                bool f = false;

                                for (int i = 0; i < c; i++) {
                                        if (r[i][0] == x && r[i][1] == y) {
                                                f = true;
                                                break;
                                        }
                                }

                                if (f == false) {
                                        r[c][0] = x;
                                        r[c][1] = y;
                                        c++;
                                }
                        } else {
                                r[c][0] = x;
                                r[c][1] = y;
                                c++;
                        }
                }
        } else {
                if ((y2-y1)/(x2-x1) == (y4-y3)/(x4-x3) && y1 - ((y2-y1)/(x2-x1) * x1) == y3 - ((y4-y3)/(x4-x3) * x3)) {
                        inf = true;
                }
        }
}