Convert a string to upper case without using built in methods/functions [closed]

Question

Challenge

You will be given a string as an argument. You need to convert that string to upper case. But you can't use any built in method or function nor any external programs.

Rule

No use of built in methods or functions or external programs. Only arithmetic, bitwise, logical operators, regex, replace, split, join, ASCII codes are allowed.

Input

The string as an argument. The string can contain spaces and special characters.

Output

The string in upper case.

This is code-golf so shortest code wins.

Answer 1

Japt, 5 bytes

;dCíB

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Answer 2

Turing Machine Code, 279 bytes

0 q Q r 0
0 w W r 0
0 e E r 0
0 r R r 0
0 t T r 0
0 y Y r 0
0 u U r 0
0 i I r 0
0 o O r 0
0 p P r 0
0 a A r 0
0 s S r 0
0 d D r 0
0 f F r 0
0 g G r 0
0 h H r 0
0 j J r 0
0 k K r 0
0 l L r 0
0 z Z r 0
0 x X r 0
0 c C r 0
0 v V r 0
0 b B r 0
0 n N r 0
0 m M r 0
0 _ _ r 0
0 * * r 0

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Answer 3

Keg, 14 bytes

(&az⑻•[& -|&],

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Finally! A challenge Keg was designed for! This utilises the fact that a) subtracting 32 from the ordinal value of any lower-case letter gives its upper-case counterpart and b) characters are treated as numbers when arithmetic is applied.

The unicode part is to ensure the letter is in the lower case range, without using built-ins.

Answer 4

05AB1E, 8 5 bytes

(Once again, a'_' uses something that I didn't know even existed in 05AB1E.)

AžpR‡

Explanation

       # Implicit input
A      # Push lowercase alphabet
 žp    # Push uppercase alphabet reversed
   R   # And reverse it again
    ‡  # Transliterate
     J # Join list

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Original solution without ‡, 19 18 bytes

εDAskD®ÊižpRèës}}J

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Explanation

                   # Implicit input
ε               }  # Loop on each character
εD              }  # Duplicate
ε A             }  # Push lowercase alphabet
ε  s            }  # Swap
ε   k           }  # Find index of character in alphabet
ε    D          }  # Duplicate for comparison
ε     ®         }  # Push -1 (see link below)
ε      Ê        }  # Check if equal
ε       i    ë }}  # If-else statement
ε       ižp  ë }}  # Push uppercase alphabet in reverse
ε       i  R ë }}  # Reverse the string (so now it's just the uppercase alphabet)
ε       i   èë }}  # Index the uppercase alphabet
ε       i    ës}}  # Swap to get character
                 J # Join all the items

If you're wondering why ® returns -1, go here

Answer 5

Batch, 245 116 Bytes

@Set v=%~1
@for %%A in (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)do @call set v=%%v:%%A=%%A%%
@ECHO(%v%

Somewhat ugly and brute forced, using a for loop to enact substring modification on each instance of a character. 129 bytes dropped thanks to Neil

Answer 6

Erlang (escript), 56 bytes

Numeric lists are strings in Erlang. (9 bytes away from C, let's see if I can get this shorter.)

f([H|T])->[H-if H>97,H<122->32;1<2->0end]++f(T);f(N)->N.

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Explanation

f([H | T]) -> % Try to split the input into head & tail
[H -          % Subtract the current item by:
if
  H > 97, H < 122 -> 32;
              % If the item's ord code is in the lowercase letter range:Return 32
  1 < 2 -> 0  % Otherwise, return 0. 1<2 is 1 byte shorter than true.
end 
] ++ f(T);    % Concatenate with the uppercased tail


f(N) -> N.    % If the tail is the null list (i.e. it can't be splitted):
              % Return this operand.
```

Answer 7

Bash + core utilities, 10 bytes

tr a-z A-Z

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Answer 8

4, 54 bytes

Thanks to @PkmnQ for pointing out the bug!

3.6993269897697017008003010098801100009960100950070094

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4, 28 bytes (old answer, only supports lower case and nothing else XD)

3.69932700800100009950070094

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Answer 9

C (gcc), ⁴⁷ 45 bytes

Saved 2 bytes thanks to ceilingcat!!!

f(char*s){for(;*s;++s)*s^=*s>96&*s<123?32:0;}

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Answer 10

APL+WIN, 28 bytes

Prompts for string:

⎕av[i-32×(i←⎕av⍳⎕)∊(97+⍳26)]

Converts string to relevant indices in APL's atomic vector, identifies indices of lower case letters, decrements only those indices by 32 and converts resulting string back to characters.

Answer 11

Charcoal, 9 bytes

⭆Ｓ§⁺αι⌕βι

Try it online! Link is to verbose version of code. Only 7 bytes longer than the built-in! Explanation:

 Ｓ          Input string
⭆           Map over characters and join
      ⌕     Find index in
       β    Lowercase alphabet of
        ι   Current character
  §         Cyclically index into
   ⁺        Concatenation of
    α       Uppercase alphabet
     ι      Current character
            Implicitly print

If the input character is not found in the lowercase alphabet, the returned index is -1, which represents the last character when passed to the cyclic index function.

Answer 12

Retina, 5 bytes

T`l`L

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Transliterate lower case letters into upper case Letters.

Answer 13

16/32/64-bit x86 assembly language, 17 bytes

AC    l1: lodsb
3C 61     cmp   al, 'a'
72 06     jb    l2
3C 7A     cmp   al, 'z'
77 02     ja    l2
24 DF     and   al, 0dfh ;convert to uppercase
AA    l2: stosb
84 C0     test  al, al
75 F0     jne   l1
C3        ret

Call with (r/e)si pointing to source string, (r/e)di to destination buffer to hold converted text.