#include <stdio.h>

int main() {
    char str[100]="welcome";
    str[0]='Z';
    printf("%s\n",str);
    
    char s[50]={'w','e','l','l'};
    s[0]='D';
    printf("%s\n",s);
    
    char *a="hello";
     *a[0]="C";
     printf("%s\n",a);
    
    return 0;
}