#include<stdio.h>
#include<string.h>
#include<ctype.h>
int main(){
    char str[100];
    int i,len,lwl=0;
    fgets(str,sizeof(str),stdin);
    str[strcspn(str,"\n")]=="\0";
    len=strlen(str)
    for(i=0;i<len;i++)
    {
        if(!(isalpha(str[i]||isspace(str[i])))){
            printf("Invaild input");
            return 0;
        }
    }
    i=len-1;
    while(i>=0&&str[i]==''){
        i--;
    }
    while(i>=0&&isalpha(str[i])){
        lwl++;
        i--;
    }
    printf("%d\n",lwl);
    return 0;
}