Swift Program to Display Alphabets (A to Z) using loop

This tutorial will discuss how to write a Swift program to display alphabets (A to Z) using loop.

In Swift, we can display alphabets starting from A to Z in both lower and upper case with the help of for-loop. Here we use the following terms in the below codes ?

Scalar ? It represents a single value.

Unicode ? It is a standard encoding for text.

UnicodeScalar ? It represents a single Unicode scalar value.

Below is a demonstration of the same ?

Suppose we enter the following input ?

A to Z

Following is the desired output ?

A B C D E F G H I J K L M N LO P Q R S T U V W X Y Z

Algorithm

The algorithm is explained below ?

• Step 1 ? Declare variables with unicode scalar value using Unicode.Scalar.value ?

  let initalAlphabet = Unicode.Scalar("A").value

  let endAlphabet = Unicode.Scalar("Z").value

  Here, Unicode.Scalar.value return the unicode value of A and Z that are 65 and 90.

• Step 2 ? Run a for loop

• Step 3 ? Print the output

Example 1

The following program shows how to display alphabets (A to Z) using for loop in upper case.

<div class="execute"></div><div class="code-mirror  language-swift" contenteditable="plaintext-only" spellcheck="false" style="outline: none; overflow-wrap: break-word; overflow-y: auto; white-space: pre-wrap;"><span class="token keyword">import</span> <span class="token class-name">Foundation</span>
<span class="token keyword">import</span> <span class="token class-name">Glibc</span>

<span class="token keyword">let</span> initalAlphabet <span class="token operator">=</span> <span class="token class-name">Unicode</span><span class="token punctuation">.</span><span class="token class-name">Scalar</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"A"</span></span><span class="token punctuation">)</span><span class="token punctuation">.</span>value
<span class="token keyword">let</span> endAlphabet <span class="token operator">=</span> <span class="token class-name">Unicode</span><span class="token punctuation">.</span><span class="token class-name">Scalar</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"Z"</span></span><span class="token punctuation">)</span><span class="token punctuation">.</span>value

<span class="token function">print</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"Following are the alphabets from A to Z:"</span></span><span class="token punctuation">)</span>
<span class="token keyword">for</span> k <span class="token keyword">in</span> initalAlphabet<span class="token operator">...</span>endAlphabet <span class="token punctuation">{</span>
   <span class="token keyword">if</span> <span class="token keyword">let</span> val <span class="token operator">=</span> <span class="token class-name">Unicode</span><span class="token punctuation">.</span><span class="token class-name">Scalar</span><span class="token punctuation">(</span>k<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token function">print</span><span class="token punctuation">(</span>val<span class="token punctuation">)</span>
   <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</div><div class="output-wrapper"><div class="console-close"></div><div class="code-output"></div></div>

Output

<span class="typ">Following</span><span class="pln"> are the alphabets </span><span class="kwd">from</span><span class="pln"> A to Z</span><span class="pun">:</span><span class="pln">
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z</span>

Here in the above code, we create two variables with values named initalAlphabet = Unicode.Scalar("A").value and endAlphabet and endAlphabet = Unicode.Scalar("Z").value. Where the Unicode.Scalar("A").value return the ASCII value of ?A? that is 65 and Unicode.Scalar("Z").value returns the ASCII value of ?Z? that is 90. Now we run a for loop from 65 to 90 and display all the Alphabet starting from A to Z using the following code ?

<span class="kwd">if</span><span class="pln"> </span><span class="kwd">let</span><span class="pln"> val </span><span class="pun">=</span><span class="pln"> </span><span class="typ">Unicode</span><span class="pun">.</span><span class="typ">Scalar</span><span class="pun">(</span><span class="pln">k</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
   </span><span class="kwd">print</span><span class="pun">(</span><span class="pln">val</span><span class="pun">)</span><span class="pln">
</span><span class="pun">}</span>

Here Unicode.Scalar() convert all the ASCII value into alphabets.

Example 2

The following program shows how to display alphabets (A to Z) using for loop in lower case.

<div class="execute"></div><div class="code-mirror  language-swift" contenteditable="plaintext-only" spellcheck="false" style="outline: none; overflow-wrap: break-word; overflow-y: auto; white-space: pre-wrap;"><span class="token keyword">import</span> <span class="token class-name">Foundation</span>
<span class="token keyword">import</span> <span class="token class-name">Glibc</span>

<span class="token function">print</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"Following are the alphabets from a to z:"</span></span><span class="token punctuation">)</span>
<span class="token keyword">for</span> char <span class="token keyword">in</span> <span class="token string-literal"><span class="token string">"abcdefghijklmnopqrstuvwxyz"</span></span> <span class="token punctuation">{</span>
   <span class="token function">print</span><span class="token punctuation">(</span>char<span class="token punctuation">)</span>
<span class="token punctuation">}</span>
</div><div class="output-wrapper"><div class="console-close"></div><div class="code-output"></div></div>

Output

<span class="typ">Following</span><span class="pln"> are the alphabets </span><span class="kwd">from</span><span class="pln"> a to z</span><span class="pun">:</span><span class="pln">
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z</span>

Here in the above code, we simply create a for loop which contains all the alphabets in the string and display each alphabet separately.

Example 3

The following program shows how to display alphabets (A to Z) using for loop in lower case.

<div class="execute"></div><div class="code-mirror  language-swift" contenteditable="plaintext-only" spellcheck="false" style="outline: none; overflow-wrap: break-word; overflow-y: auto; white-space: pre-wrap;"><span class="token keyword">import</span> <span class="token class-name">Foundation</span>
<span class="token keyword">import</span> <span class="token class-name">Glibc</span>
<span class="token function">print</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"Following are the Alphabets: "</span></span><span class="token punctuation">)</span>
<span class="token keyword">for</span> val <span class="token keyword">in</span> <span class="token class-name">UnicodeScalar</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"a"</span></span><span class="token punctuation">)</span><span class="token punctuation">.</span>value<span class="token operator">...</span><span class="token class-name">UnicodeScalar</span><span class="token punctuation">(</span><span class="token string-literal"><span class="token string">"z"</span></span><span class="token punctuation">)</span><span class="token punctuation">.</span>value<span class="token punctuation">{</span> 
   <span class="token function">print</span><span class="token punctuation">(</span><span class="token class-name">UnicodeScalar</span><span class="token punctuation">(</span>val<span class="token punctuation">)</span><span class="token operator">!</span><span class="token punctuation">)</span> 
<span class="token punctuation">}</span>
</div><div class="output-wrapper"><div class="console-close"></div><div class="code-output"></div></div>

Output

<span class="typ">Following</span><span class="pln"> are the </span><span class="typ">Alphabets</span><span class="pun">:</span><span class="pln"> 
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z</span>

Here in the above code, we create for loop starting from UnicodeScalar("a").value to UnicodeScalar("z").value and display all the alphabets. Where UnicodeScalar().value returns the ASCII value of "a" and "z". UnicodeScalar() function is used to convert the ASCII to the character.