Balanced Brackets

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

int isBal(const char *s, int l)
{
    signed c = 0;

    while (l--)
    {
        if (s[l] == ']')
        {
            ++c;
        }

        else if (s[l] == '[')
        {
            if (--c < 0) break;
            {
                return !c;
            }
        }
    }
}


void shuffle(char *s, int h)
{
    int x, t, i = h;

    while (i--)
    {
        t = s[x = rand() % h];
        s[x] = s[i];
        s[i] = t;
    }

}


void genSeq(char *s, int n)
{
    if (n)
    {
        memset(s, '[', n);
        memset(s + n, ']', n);
        shuffle(s, n * 2);
    }

    s[n * 2] = 0;
}


void doSeq(int n)
{
    char s[64];
    const char *o = "False";
    genSeq(s, n);

    if (isBal(s, n * 2))
    {
        o = "True";
    }
    printf("'%s': %s\n", s, o);
}

int main()
{
    int n = 0;

    while (n < 9)
    {
        doSeq(n++);
    }
    return 0;

}

OUTPUT

'': False
'][': True
'][[]': True
'[][[]]': False
'[][[][]]': False
'[][[[][]]]': False
'][[]]][[[]][': True
'[][[[]][][]]][': True
'][[][][[[[]]][]]': False