#include<stdio.h>
#include<string.h>
#include<ctype.h>
int create_equilateral_triangle(char *name) {
   int len = strlen(name);
   if(len < 1 || len > 10) {
       printf("Invalid input");
       return 0;
   }
   for(int i=0;i<len;i++) {
       if (!isalpha(name[i])) {
           printf("Invalid input");
           return 0;
       }
   }
   for(int i=1;i<=len;i++) {
       for(int j=1;j<len;j++) {
           printf(" ");
       }
       for(int j=0;j<i;j++) {
           printf("%c",name[j]);
           if(j < i -1){
               printf(" ");
           }
       }
       printf("\n");
   }
   return 1;
}
int main() {
    char name[i];
    printf(" ");
    fgets(name, sizeof(name), stdin);
    name[strcspn(name, "\n")]='\0';
    create_equilateral_triangle(name);
    return 0;
}