[count num of character '' in string] use recursive

#icclude<stdio.h>
#include<string.h>
void split(char *s, char *s1, char *s2)
{
    int l, m;
    l = strlen(s);
    m = l/2;
    for (int i = 0; i < m; ++i)
    {
        s1[i] = s[i];
        s2[i] = s[l - m + i];
    }
}
int numofA(char *s)
{
    int count;
    count = 0;
    for (int i = 0; i < strlen(s); ++i)
    {
        if(s[i] == 'A')
            count++;
    }
    return count;
}
int countnumofAinstr(char *s)
{
    int result;
    char *s1, *s2;
    result = numofA(s);
    if(strlen(s) > 1)
    {
        split(s,s1,s2);
        result = countnumofAinstr(s1) + countnumofAinstr(s1);
    }
    return result;
}
int main(int argc, char const *argv[])
{
    char *s = "AEEAEEAAE";
    printf("%d\n", countnumofAinstr(s));
    return 0;
}