Allmän lösning klar

#include <iostream>
#include <vector>
#include <string>

using namespace std;

vector<string> split(string a, char c) {
    vector<string> ekvVector;
    string tmp = "";
    for (int i = 0; i < a.size(); i++) {
        if (a[i] == c) {
            ekvVector.push_back(tmp);
            tmp = "";
        } else {
            tmp += a[i];
        }
    }
    if (tmp != "") ekvVector.push_back(tmp);
    return ekvVector;
}
int skitMetod(string a, int yType) {
    int endResult = 0;
    int bPos = 0;
    int ePos = 0;
    for (int i = 0; i < a.size(); i++) {
        if (a[i] == 'y') {

            if (a.find("y(") != string::npos || a.find("y'(") != string::npos) {
                if (yType == 3) {
                    int parPos1 = 0;
                    for (int i = 0; i < a.length(); i++) {
                        if (a[i] == ')') {
                            parPos1 = i;
                        }
                    }
                    bPos = i;
                    if (a.find("'") != string::npos) {
                        a.erase(bPos, 3);
                        parPos1 -= 3;
                    } else {
                        a.erase(bPos, 2);
                        parPos1 -= 2;
                    }
                    if (a.find("-") != string::npos) {
                        a.erase(parPos1, 4);
                    } else {
                        a.erase(parPos1, 3);
                    }

                }
            } else {
                bPos = i;
                if (yType == 0) {
                    a.erase(bPos, 3);

                } else if (yType == 1) {
                    a.erase(bPos, 2);

                } else if (yType == 2) {
                    a.erase(bPos, 1);

                }
            }
        }
        if (a != "") {
            endResult = stoi(a);
        } else if (a.find("-") != string::npos) {
            endResult = stoi(a);
            endResult *= (-1);
        } else {
            endResult = 1;
        }
        return endResult;
    }
}

int main() {
    string ekvString = "";
    vector<string> ekvList;
    cout << "Skriv in din ekvation i formen av ay''+by'+cy (minus skrivs +- t.ex ay''+-by'+y)" << "\n";
    cin >> ekvString;
    cout << "\n";
    ekvList = split(ekvString, '+');
    double a, b, c;
    string yBis = "yBis";
    cout << ekvList.size() << "\n";
    for (int i = 0; i < ekvList.size(); i++) {
        if (ekvList[i].find("y''") != string::npos) {
            cout << "y'' found: " << skitMetod(ekvList[i], 0) << "\n";
            a = skitMetod(ekvList[i], 0);
        } else if (ekvList[i].find("y'") != string::npos && !(ekvList[i].find("y''") != string::npos)) {
            cout << "y' found : " << skitMetod(ekvList[i], 1) << "\n";
            b = skitMetod(ekvList[i], 1);
        } else if (ekvList[i].find("y") != string::npos && !(ekvList[i].find("y''") != string::npos) && !(ekvList[i].find("y'") != string::npos)) {
            cout << "y found : " << skitMetod(ekvList[i], 2) << "\n";
            c = skitMetod(ekvList[i], 2);
        }
    }
    /*
    for (int i = 0; i < ekvList.size(); i++) {
        if (ekvList[i].find(yBis) != string::npos) {
            cout << "yBis found!" << "\n";
            cout << skitMetod(ekvList[i], 0) << "\n";
            a = skitMetod(ekvList[i], 0);
        } else if (ekvList[i].find("yPrim") != string::npos) {
            cout << "yPrim found!" << "\n";
            cout << skitMetod(ekvList[i], 1) << "\n";
            b = skitMetod(ekvList[i], 1);
        } else if (ekvList[i].find("yF") != string::npos) {
            cout << "yF found!" << "\n";
            cout << skitMetod(ekvList[i], 2) << "\n";
            c = skitMetod(ekvList[i], 2);
        }
    }
    */
    b = b / a;
    c = c / a;

    double root1 = ((b / 2)*(-1)) + (sqrt((b / 2)*(b / 2) - c));
    double root2 = ((b / 2)*(-1)) - (sqrt((b / 2)*(b / 2) - c));


    cout << "\n" << "Allm\x84na l\x94sningen: " << "C1e^(" << root1 << "x) + C2e^(" << root2 << "x)\n" << "\n";
    string yLösning = "";
    string yPrimLösning = "";

    cout << "Skriv in l\x94sning p\x86 ekvationen i form av y(x)=z\n";
    cin >> yLösning;
    cout << "Skriv in l\x94sning p\x86 ekvationen i form av y'(x)=z\n";
    cin >> yPrimLösning;
    cout << "\n";
    vector<string> lösningarVector = split(yLösning, '=');
    vector<string> lösningPrimVector = split(yPrimLösning, '=');
    int xVärde = skitMetod(yLösning, 3);
    int xPrimVärde = skitMetod(yPrimLösning, 3);
    int yLösningInt = stoi(lösningarVector[1]);
    int yPrimLösningInt = stoi(lösningPrimVector[1]);

    double c1;
    double c2;
    double e = 2.71828182;

    c1 = (((yLösningInt*(root2*pow(e, root2*xPrimVärde)))) - (pow(e, root2*xVärde))*(yPrimLösningInt)) / ((pow(e, root1*xVärde))*(root2*pow(e, root2*xPrimVärde)) - (pow(e, root2*xVärde))*(root1*pow(e, root1*xPrimVärde)));
    c2 = (((pow(e, root1*xVärde))*(yPrimLösningInt)) - ((yLösningInt)*(root1*pow(e, root1*xPrimVärde)))) / ((pow(e, root1*xVärde))*(root2*pow(e, root2*xPrimVärde)) - (pow(e, root2*xVärde))*(root1*pow(e, root1*xPrimVärde)));


    cout << "C1 = " << c1 << "\n";
    cout << "C2 = " << c2 << "\n\n";
    //c1 = ylösningsint    c2=yprimlösningsint b1=e^(root2*xvärde) b2=root2*e^(root2*xprimvärde) a1 = e^(root1*xvärde) a2 = root1*e^(root1*xprimvärde)

#ifdef _DEBUG
    system("pause");
#endif // _DEBUG
}