wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
let index: Int = 'hello' | let index: String = 'hello' | Fix type. | Swift |
if val = 32 {{}} | if val == 32 {{}} | Use ==. | Swift |
switch(z){{ case 81: break; }} | switch(z){{ case 81: break; default: break; }} | Add default case. | Java |
echo 'test' | echo 'test'; | Add semicolon. | PHP |
<div><p>world</div></p> | <div><p>world</p></div> | Nest properly. | HTML |
foo = output | foo = 'output' | Quote strings. | Python |
def handle
puts 'data'
end | def handle
puts 'data'
end | Correct. | Ruby |
int* obj = nullptr; *obj=5; | int* obj = new int; *obj=5; | Allocate memory. | C++ |
disp('message') | disp('message') | Correct. | MATLAB |
JOIN products ON products.id = products.id | JOIN products ON products.id = products.id | Correct. | SQL |
name: value
age: 46 | name: value
age: 46 | Correct. | YAML |
let temp = 'output' | let temp = "output" | Double quotes. | Swift |
[36, 99, 62 | [36, 99, 62] | Close bracket. | Python |
class Item {{ int count; }}
obj.count=5; | class Item {{ public int count; }}
obj.count=5; | Make field public. | Java |
x := 40 | x := 40 | Correct. | Go |
<br></br> | <br> | Self-closing. | HTML |
if (y = 41) | if (y == 41) | Use ==. | R |
if ($x = 4) | if ($x == 4) | Use ==. | Perl |
let result: i32 = "test"; | let result: &str = "test"; | Type mismatch. | Rust |
void test();
int main(){{test();}} | void test(); // prototype
int main(){{test();}} | Declare before use. | C++ |
div {{ color=blue; }} | div {{ color: blue; }} | Use colon. | CSS |
arr.forEach(function(val) {{ console.log(val); }}) | arr.forEach((val) => {{ console.log(val); }}) | Arrow functions are cleaner. | JavaScript |
switch(bar){{ case 88: break; }} | switch(bar){{ case 88: break; default: break; }} | Add default case. | Java |
c = 11 | c=11 | No spaces. | Shell |
$items[64] | if ($items.Count -gt 64) {{ $items[64] }} | Check bounds. | PowerShell |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
val x = 'world' | val x = "world" | Double quotes. | Kotlin |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
if (x = 19) {{}} | if (x === 19) {{}} | Use === for equality. | JavaScript |
if y = 44 {{}} | if y == 44 {{}} | Use ==. | Swift |
if foo = 90: | if foo == 90: | Use == for comparison. | Python |
{{'value':'test'}} | {{"value":"test"}} | Use double quotes. | JSON |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
{{"name":"result",}} | {{"name":"result"}} | Remove trailing comma. | JSON |
const result; | const result = 1; | Initialize const. | JavaScript |
String name = 'value'; | String name = 'value'; | Correct. | Dart |
fmt.Println 'message' | fmt.Println('message') | Missing parentheses. | Go |
bar | bar() | Add parentheses. | Swift |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
DELETE FROM products WHERE age=72 | DELETE FROM products WHERE age=72; | Add semicolon. | SQL |
val x: Int = 'result' | val x: String = 'result' | Fix type. | Kotlin |
JOIN orders ON products.id = orders.status | JOIN orders ON products.id = orders.status | Correct. | SQL |
System.out.println('world') | System.out.println('world'); | Add semicolon. | Java |
echo message data | echo 'message data' | Quote to prevent splitting. | Shell |
id: value
age: data, | id: value
age: data | Remove comma. | YAML |
$items[10] = 5; | if (isset($items[10])) $items[10] = 5; | Check existence. | PHP |
fs.readFile('data.txt', (err,data) => {{ if(err) throw err; }}); | fs.readFile('data.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }}); | Better error handling. | Node.js |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
items(75) | if length(items) >= 75, items(75), end | Check length. | MATLAB |
[79, 80, 42 | [79, 80, 42] | Close bracket. | Python |
object Order {{ def main(args: Array[String]) = println("test") }} | object Order {{ def main(args: Array[String]): Unit = println("test") }} | Add return type Unit. | Scala |
String a = 'result'; | String a = "result"; | Double quotes. | Java |
raise 'info' | raise Exception('info') | Raise needs an exception class. | Python |
#footer {{ color: red; }} | #footer {{ color: red; }} | Correct. | CSS |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
disp('hello') | disp('hello') | Correct. | MATLAB |
SELECT * FROM products WHRE name=35; | SELECT * FROM products WHERE name=35; | Fix WHERE. | SQL |
function handle(z:string){{return z;}} handle(49); | function handle(z:string){{return z;}} handle('test'); | Pass correct type. | TypeScript |
$x = 5; if ($x -eq 5) { Write-Host 'yes' } | $x = 5; if ($x -eq 5) { Write-Host 'yes' } | Correct. | PowerShell |
List<int> list = [1,2,3]; | List<int> list = [1,2,3]; | Correct. | Dart |
print('world') | print('world') | Correct. | R |
<a href='https://demo.net' target='_blank'> | <a href='https://demo.net' target='_blank' rel='noopener'> | Add rel for security. | HTML |
yield bar | yield bar | Correct yield. | Python |
re.sqrt(94) | import re
re.sqrt(94) | Import module first. | Python |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
if ($result = 3) | if ($result == 3) | Use ==. | Perl |
function handle(): void {{ return 23; }} | function handle(): number {{ return 23; }} | Return type mismatch. | TypeScript |
let a = 74; a += 1; | let mut a = 74; a += 1; | Need mut to modify. | Rust |
if count = 55 | if count == 55 | Use ==. | MATLAB |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
let val: number = 'info'; | let val: string = 'info'; | Fix type. | TypeScript |
println('test') | println("test") | Double quotes. | Scala |
if (val = 100) | if (val == 100) | Use ==. | C++ |
const p:Person = {{name:'world'}}; | const p:Person = {{name:'world', age:22}}; | Add missing property. | TypeScript |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
'hello' + 45 | 'hello' + str(45) | Can't add int to string. | Python |
if (bar) console.log('yes') else console.log('no') | if (bar) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
cin >> bar
cout << bar; | cin >> bar;
cout << bar; | Add semicolon. | C++ |
handle | handle() | Add parentheses. | Kotlin |
list[49] | if (length(list) >= 49) list[49] | Check length. | R |
if result = 85 | if result == 85 | Use ==. | Go |
val y = 54; y = 39 | var y = 54; y = 39 | Use var for reassignment. | Scala |
INSERT INTO items VALUES ('value',12) | INSERT INTO items (age, email) VALUES ('value',12); | Specify columns. | SQL |
let bar: Int = 'message' | let bar: String = 'message' | Fix type. | Swift |
{{'id':63, 'id' 98}} | {{'id':63, 'id':98}} | Colon missing. | Python |
if bar > 86
print('message') | if bar > 86:
print('message') | Colon missing after if. | Python |
<br></br> | <br> | Self-closing. | HTML |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
{{"title":"output" "id":10}} | {{"title":"output", "id":10}} | Add comma. | JSON |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
$item = 61; if ($item = 61) {{}} | $item = 61; if ($item == 61) {{}} | Use ==. | PHP |
my @arr = (42,24,41); | my @arr = (42,24,41); | Correct. | Perl |
function handle() {{
return
{{key:'result'}}
}} | function handle() {{
return {{key:'result'}};
}} | Return object on same line. | JavaScript |
echo 'message' | echo 'message'; | Add semicolon. | PHP |
if temp > 40
puts 'test' | if temp > 40
puts 'test'
end | Add 'end'. | Ruby |
List(86,2,24) | List(86,2,24) | Correct. | Scala |
<div><p>data</div></p> | <div><p>data</p></div> | Nest properly. | HTML |
40val = 10 | val40 = 10 | Variable cannot start with digit. | Python |
if x = 57 then
print('output')
end | if x == 57 then
print('output')
end | Use ==. | Lua |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.