Calculate the occurrences of a character in C lang.

occurrences.c

#include<stdio.h>
/*
Author:nacer salah eddine.
Description:Calculate the occurrences of a character in C lang.
Compile:
gcc occurrences.c -std=c99 -Wall -o occurrences
*/
size_t occurrences_of_char(const char s,const char* str){
    
    /*
    printf("%c\n",s);
    printf("First char:%c\n",*str);
    printf("%s\n",str);
    */
    register const char *p = str;
    int occ = 0;
    for(;*p;++p)if(*p == s)occ++;
    

    return occ;
}

int main(){

const char *string = "hello bad world\0";
const char c = 'l';
size_t occurences = occurrences_of_char(c,string);
printf("%d\n",occurences);

return 0;
}