Parallel Arrays and Records

class parallelarrays {

    public static int[] SID = new int[100];
    public static String[] SNAME = new String[100];
    public static int[] MTH = new int[100];
    public static int[] ENG = new int[100];
    public static int[] CHI = new int[100];
    public static int N=-1;

    public static void main(String[] args) {
        insertStudent(123, "JACKY");
        insertStudent(231, "JASPER");
        insertStudent(333, "TOMMY");
        insertStudent(787, "ISAAC");
        insertStudent(999, "DENNIS");
        updateMTH(999, 85);
    }

    public static void insertStudent(int stuid, String sname) {
        N++;
        if (N<100) {
            SID[N] = stuid;
            SNAME[N] = sname;
            MTH[N] = 0;
            ENG[N] = 0;
            CHI[N] = 0;
        }
    }

    public static boolean updateName(int stuid, String sname) {
        int id;
        boolean result;
        id = searchByStuid(stuid);
        if (id != -1) {
            SNAME[id] = sname;
            result = true;
        } else {
            result = false;
        }
        return result;
    }

    public static int searchByStuid(int stuid) {
        int id=-1;
        int i = 0;
        while (i<100 && id==-1) {
            if (SID[i] == stuid) {
                id = i;
            }
            i++;
        }
        return i;
    }

    public static boolean updateMTH(int stuid, int mark) {
        int id;
        boolean result;
        id = searchByStuid(stuid);
        if (id != -1) {
            MTH[id] = mark;
            result = true;
        } else {
            result = false;
        }
        return result;
    }

    public static boolean updateCHI(int stuid, int mark) {
        int id;
        boolean result;
        id = searchByStuid(stuid);
        if (id != -1) {
            CHI[id] = mark;
            result = true;
        } else {
            result = false;
        }
        return result;
    }

    public static boolean updateENG(int stuid, int mark) {
        int id;
        boolean result;
        id = searchByStuid(stuid);
        if (id != -1) {
            ENG[id] = mark;
            result = true;
        } else {
            result = false;
        }
        return result;
    }

}