fizzbuzz.c

#define NUMBER *p-- = buf; itoa(i, buf); while (*buf++); --i;
#define FIZZ *p-- = "Fizz"; --i;
#define BUZZ *p-- = "Buzz"; --i;
#define FIZZBUZZ *p-- = "FizzBuzz"; --i;

void itoa(int value, char* s) {
    int l;
    if (value > 9999) l = 5;
    else if (value > 999) l = 4;
    else if (value > 99) l = 3;
    else if (value > 9) l = 2;
    else l = 1;
    s[l] = '\0';
    while (l > 0) {
        s[--l] = (value % 10) + '0';
        value /= 10;
    }
}

char mem[1024*128];
char ** fizzBuzz(int n, int* returnSize){
    char* buf = mem;
    char** v = (void*) buf;
    buf += sizeof(char*)*n;
    *returnSize = n;
    
    int i = n;
    while (i > 0) {
        char** p = &v[i-1];
        switch (i%15) {
        case 14: NUMBER
        case 13: NUMBER
        case 12: FIZZ
        case 11: NUMBER
        case 10: BUZZ
        case 9: FIZZ
        case 8: NUMBER
        case 7: NUMBER
        case 6: FIZZ
        case 5: BUZZ
        case 4: NUMBER
        case 3: FIZZ
        case 2: NUMBER
        case 1: NUMBER
        case 0:
            if (i == 0) break;
            FIZZBUZZ
        }
    }
    
    return v;
}