// editor1
#include<stdio.h>
#include<string.h>
int main()
{
    char str[101];
    int seen[256];
    int i,j=0;
    char result[101];
    fgets(str,sizeof(str),stdin);
    str[strcspn(str,"\n")]='\0';
    for(i=0;str[i] != '\0';i++)
    {
        if(!(isalnum(str[i]) || str[i]==''))
    }
    printf("invalid input");
    return 0;
}