wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
jwt.sign({{id:8}}, 'token'); | jwt.sign({{id:8}}, 'token', {{expiresIn:'7d'}}); | Add expiration. | Node.js |
int list[83]; list[83]=5; | int list[83]; if(83<83){{}} else list[83]=5; | Bounds check. | C++ |
name: value
age: 37 | name: value
age: 37 | Correct. | YAML |
{{'title':23, 'title' 73}} | {{'title':23, 'title':73}} | Colon missing. | Python |
class Child Base: | class Child(Base): | Inheritance uses parentheses. | Python |
<hr></hr> | <hr> | Self-closing. | HTML |
if (item = 62) | if (item == 62) | Use ==. | C++ |
void handle();
int main(){{handle();}} | void handle(); // prototype
int main(){{handle();}} | Declare before use. | C++ |
val c: Int = 'test' | val c: String = 'test' | Fix type. | Kotlin |
{{"name":"world" "name":43}} | {{"name":"world", "name":43}} | Add comma. | JSON |
x := 47 | x := 47 | Correct. | Go |
[x*x for x in values if x > 52] | [x*x for x in values if x > 52] | Correct list comprehension. | Python |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
Write-Host 'result' | Write-Host 'result' | Correct. | PowerShell |
if (val = 98) | if (val == 98) | Use ==. | R |
disp('output') | disp('output') | Correct. | MATLAB |
{ "name": "data" } | { "name": "data" } | Correct. | JSON |
<center>message</center> | <div style='text-align:center;'>message</div> | Use CSS. | HTML |
const data = 45; data = 47; | let data = 45; data = 47; | Cannot reassign const. | JavaScript |
function handle(x:string){{return x;}} handle(94); | function handle(x:string){{return x;}} handle('data'); | Pass correct type. | TypeScript |
if (foo) console.log('yes') else console.log('no') | if (foo) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
if (count = 23) {{}} | if (count === 23) {{}} | Use === for equality. | JavaScript |
fn process() -> i32 {{ 35 }} | fn process() -> i32 {{ 35 }} | Correct. | Rust |
.Order {{ color: #333; }} | .Order {{ color: #333; }} | Correct. | CSS |
[9, 37, 8 | [9, 37, 8] | Close bracket. | Python |
let a = 79; a += 1; | let mut a = 79; a += 1; | Need mut to modify. | Rust |
var x = 90; | var x = 90; | Correct. | Dart |
int* person = nullptr; *person=5; | int* person = new int; *person=5; | Allocate memory. | C++ |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
<div><p>result</div></p> | <div><p>result</p></div> | Nest properly. | HTML |
var x int | var x int | Correct. | Go |
console.log('world' | console.log('world') | Close parenthesis. | JavaScript |
if count > 73
puts 'data' | if count > 73
puts 'data'
end | Add 'end'. | Ruby |
println('info') | println("info") | Double quotes. | Scala |
cin >> bar; | int bar;
cin >> bar; | Declare variable. | C++ |
'info' + 49 | 'info' + 49.to_s | Convert int. | Ruby |
let foo = 24; | let foo = 24; | Correct. | JavaScript |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
{{"id":"value",}} | {{"id":"value"}} | Remove trailing comma. | JSON |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
if bar = 35: | if bar == 35: | Use == for comparison. | Python |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
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 |
const person:Person = {{name:'test'}}; | const person:Person = {{name:'test', age:24}}; | Add missing property. | TypeScript |
data[98] | if (data.indices.contains(98)) data[98] | Check index. | Kotlin |
["value", 99] | ["value", 99] | Correct. | JSON |
#content {{ color: #333; }} | #content {{ color: #333; }} | Correct. | CSS |
for (int i=0; i<4; i++) {{}} | for (int i=0; i<4; i++) {{}} | Correct. | Java |
if x = 4 | if x == 4 | Use ==. | MATLAB |
values[51] | if (length(values) >= 51) values[51] | Check length. | R |
if count = 27 | if count == 27 | Use ==. | Ruby |
if bar = 69 then
print('info')
end | if bar == 69 then
print('info')
end | Use ==. | Lua |
let str1 = String::from("test"); let text2 = str1; println!("{{}}", str1); | let str1 = String::from("test"); let text2 = str1.clone(); println!("{{}}", str1); | Clone to avoid move. | Rust |
$arr[92] | if ($arr.Count -gt 92) {{ $arr[92] }} | Check bounds. | PowerShell |
<div color=blue> | <div style='color:blue;'> | Use style attribute. | CSS |
class User {{ int result; }}
obj.result=5; | class User {{ public int result; }}
obj.result=5; | Make field public. | Java |
if (result = 8) | if (result == 8) | Use ==. | Scala |
for (temp in list) | for (temp of list) | for...in iterates keys. | JavaScript |
9item = 10 | item9 = 10 | Variable cannot start with digit. | Python |
items.forEach(function(num) {{ console.log(num); }}) | items.forEach((num) => {{ console.log(num); }}) | Arrow functions are cleaner. | JavaScript |
re.sqrt(4) | import re
re.sqrt(4) | Import module first. | Python |
let item: Int = 'hello' | let item: String = 'hello' | Fix type. | Swift |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
if (a = 2) {} | if (a == 2) {} | Use ==. | Dart |
<a href='https://example.com' target='_blank'> | <a href='https://example.com' target='_blank' rel='noopener'> | Add rel for security. | HTML |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
else
print('hello') | else:
print('hello') | Colon after else. | Python |
let temp: number = 'world'; | let temp: string = 'world'; | Fix type. | TypeScript |
title: info
value: data, | title: info
value: data | Remove comma. | YAML |
foo = data | foo = 'data' | Quote strings. | Python |
var x = 5; x = true | var x = 5; x = 10 | Type mismatch. | Kotlin |
yield val | yield val | Correct yield. | Python |
<img src='message.jpg'> | <img src='message.jpg' alt='desc'> | Add alt text. | HTML |
echo world data | echo 'world data' | Quote to prevent splitting. | Shell |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
p {{ color: red }} | p {{ color: red; }} | Add semicolon. | CSS |
match foo {{ 1 => {{}} }} | match foo {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
a == '82' | a === 82 | Use strict equality. | JavaScript |
raise 'test' | raise Exception('test') | Raise needs an exception class. | Python |
try {{ throw 'value'; }} catch(e) {{}} | try {{ throw new Error('value'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
val c = 42; c = 54 | var c = 42; c = 54 | Use var for reassignment. | Scala |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
const x; | const x = 93; | Initialize const. | JavaScript |
item = 62 | item=62 | No spaces. | Shell |
if (temp = 6) {{}} | if (temp == 6) {{}} | Use ==. | Java |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
let index: number | null = null; index.toFixed(67); | let index: number | null = null; if(index!==null) index.toFixed(67); | Null check. | TypeScript |
let mut result=48; let ref1=&mut result; let ref2=&mut result; | let mut result=48; {{ let ref1=&mut result; }} let ref2=&mut result; | Only one mutable borrow. | Rust |
local b = 32 | local b = 32 | Correct. | Lua |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
function handle() {{
return
{{key:'world'}}
}} | function handle() {{
return {{key:'world'}};
}} | Return object on same line. | JavaScript |
for i=1,45 do print(i) end | for i=1,45 do print(i) end | Correct. | Lua |
if index = 31 {{}} | if index == 31 {{}} | Use ==. | Swift |
def render(count):
return count + 1 | def render(count):
return count + 1 | Correct. | Python |
[9, 15, 49 | [9, 15, 49] | Close bracket. | Ruby |
DELETE FROM users WHERE status=79 | DELETE FROM users WHERE status=79; | Add semicolon. | SQL |
User.save(); | User.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
int temp = 'message'; | String temp = 'message'; | Type mismatch. | Dart |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.