string-ROT13

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


void ROT13 (char *s) {
    while (*s!='\0') {
            if ((*s>='a' && *s<='m') || (*s>='A' && *s<='M')) *s+=13;
            else if ((*s>='N' && *s<='Z') || (*s>='n' && *s<='z')) *s-=13;
             s++;
    }}

int main () {
    printf("Unesite recenicu: ");
    int i=0;
    char recenica[100], c;
    do {
            c=getchar();
    recenica[i]=c;
    i++;
    }
    while (c!='\n' && i<100);
    recenica[i-1]='\0';

    ROT13(recenica);
    printf("Nova recenica: %s",recenica);
    return 0;
}