#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\n");
        return 0;
    }
    for (int i = 0; i<len;i++)
    {
        if (isdigit(name[i]))
        {
            printf("Invalid input\n");
            return 0;
        }
    }
    for (int i = 1; i <= len;i++)
    {
        for (int j = 0;j<i;j++)
        {
            printf(" ");
        }
    }
    printf("\n");
}
return 1;
}

int main()
{
    char name[11];
    
    printf(" ");
    fgets(name, sizeof(name), stdin);
    
    name[strcpy(name, "\n")] = '\0';
    
    create_equilateral_triangle(name);
    
    return 0;
}