Collatz generalization stuff

#include <iostream>
#include <cmath>
bool in_array (int needle, int haystack[5000]) {
    for (int i = 0; haystack[i] != -1; i++) {
        if (needle == haystack[i]) return true;
    } return false;
}
void add (int needle, int haystack[5000]) {
    int i = 0;
    while (haystack[i] != -1) i++;
    if (haystack[i] == -1) {
        haystack[i] = needle;
        haystack[i+1] = -1;
    }
}
void print (int haystack[5000]) {
    for (int i = 0; haystack[i] != -1; i++) {
        printf("%i ",haystack[i]);
    }
    printf("\n");
}
int length (int haystack[5000]) {
    int li = 0;
    for (int i = 0; haystack[i] != -1; i++) {
        li++;
    }
    return li;
}
int valuation (int base, int number) {
    if (number % base != 0) return 0;
    if (number == 0) return -1661992959; else {
        int c = number;
        int i = 0;
        while (c % base == 0) {
            c /= base;
            i++;
        }
        return i;
    }
}
int powval (int base, int number) {
    int val = valuation(base, number);
    int prod = 1;
    if (val <= 0) return prod; else {
        for (int i = 0; i < val; i++) {
            prod *= base;
        }
        return prod;
    }
}
int collatz (int number, int base = 2) {
    if (number % base == 0) return number/powval(base,number); else {
        int num = (int(number/base) + number + 1);
        return num/powval(base,num);
    }
}
int main (int, char **) {
    int i,j;
    int now;
    bool dowhile, overall;
    int haystack[5000];
    int yeetsack[5000];
    for (int step = 2; step <= 250/4; step++) {
        goto yeeeet;
        yeet2:
        printf("b = %i, m != n and a_m = a_n = ... : ",step-1);
        print(yeetsack);
        yeeeet:
        yeetsack[0] = -1;
        for (i = step; i < 100000000; i++) {
            dowhile = false;
            haystack[0] = i;
            haystack[1] = -1;
            j = i;
            while (!in_array(collatz(j,step),haystack) and collatz(j,step) >= step) {
                add(collatz(j,step),haystack);
                j = collatz(j,step);
            }
            add(collatz(j,step),haystack);
            now = haystack[length(haystack)-1];
            if (now <= 0) dowhile = true;
            if (!in_array(now,yeetsack)) {
                add(now,yeetsack);
            }
            overall = true;
            for (int k = 0; k < step; k++) {
                if (in_array(k,haystack)) overall = false;
            }
            if ((dowhile or now < 0 or now >= step) and overall) {
                i = 0; step++;
                if (now < 0) {
                    haystack[length(haystack)-1] = -1;
                    yeetsack[length(yeetsack)-1] = -1;
                }
                if (now >= step) {
                    printf("   (doesn't work) b = %i, m != n and a_m = a_n = ... : ",step-1);
                    print(yeetsack);
                    goto yeeeet;
                }
                goto yeet2;
            }
        }
        printf("b = %i, m != n and a_m = a_n = ... : ",step);
        print(yeetsack);
    }
}