我的 CS50 mario 不太舒服的代码有什么问题？

Question

Here is a copy of my code:

#include <cs50.h>
#include <stdio.h>

int main(void)
{
    int height = get_int("Please enter a height between 1 and 8 (inclusive)\nHeight: ");

    if(0 < height && height < 9)
    for(int i = 0; i <= height; i++)
    {
        for(int s = (height - 1); s >= 1; s--)
        {
            printf("a");
        }

        for(int h = 1; h <= i; h++)
        {
            printf("#");
        }

        printf("\n");
    }

    else
    printf("Please try again.\n"),
    main();
}

The part I cannot seem to get right is printing the correct number of spaces as it does not seem to reduce the variable "s" after each loop. (I have replaced the spaces with the letter "a" so I can see where the code has gone wrong.) The aim of the code is to print a pyramid of #'s that is right-aligned. Where have I gone wrong here?

So for example, if the user inputs a height of 3, the output will be:

aa

aa#

aa##

aa###

however, I would like the output to be:

aa#

a##

###

Answer 1

The main issue is the 2nd for loop in your code when you print "a". Everytime you hit in this particular loop, you basically print (height - 1) times "a". In fact, you should print every time one less "a" (and one more hashes). To achieve this, we need to tweak condition of s. Instead of this

int s = height - 1; s >= 1

Use this

int s = height - i; s > 1

Since your main loop has iterator i , we can use it here.

Second issue is that according to CS50 problem set description, you should actually print " " (spaces), not "a" . For this, you should replace "a" with " " .

Third issue is your code prints an extra line with full of space in the begining. You need to tweak the main for loop with this condition to remove one extra line.

i < height

And in the for loop where you print # symbol, you need to start iterator h from zero, so that it prints right away with the first line.

int h = 0

Answer 2

The better solution is to use the built-in functionality of printf that is already in place, reducing the problem to a single, simple loop.

#include <stdio.h>

int main(void) {
    int height = get_int("Please enter a height between 1 and 8 (inclusive)\nHeight: ");

    unsigned char blocks[height];
    memset(blocks, '#', height);

    for(int i=0; i<height; ++i)
    {
        printf("%*.*s\n", height, i+1, blocks);
    }
    return 0;
}

Output

Success #stdin #stdout 0s 4212KB
    #
   ##
  ###
 ####
#####