wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
<img src='output.jpg'> | <img src='output.jpg' alt='desc'> | Add alt text. | HTML |
class Child Base: | class Child(Base): | Inheritance uses parentheses. | Python |
let count: Int = 'info' | let count: String = 'info' | Fix type. | Swift |
System.out.println('result') | System.out.println('result'); | Add semicolon. | Java |
p {{ color: red }} | p {{ color: red; }} | Add semicolon. | CSS |
let foo: number = 'result'; | let foo: string = 'result'; | Fix type. | TypeScript |
class Item {{ int b; }}; | class Item {{ public: int b; }}; | Make public. | C++ |
if (data) console.log('yes') else console.log('no') | if (data) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
list.forEach(function(item) {{ console.log(item); }}) | list.forEach((item) => {{ console.log(item); }}) | Arrow functions are cleaner. | JavaScript |
if count = 81 then
print('value')
end | if count == 81 then
print('value')
end | Use ==. | Lua |
SELECT COUNT(*) FROM orders | SELECT COUNT(*) FROM orders; | Missing semicolon. | SQL |
if ($val = 87) | if ($val == 87) | Use ==. | Perl |
$item = 22; if ($item = 22) {{}} | $item = 22; if ($item == 22) {{}} | Use ==. | PHP |
data(23) | if length(data) >= 23, data(23), end | Check length. | MATLAB |
<person><age>value</age><age>11</age></person | <person><age>value</age><age>11</age></person> | Add closing >. | XML |
if (b = 12) {{}} | if (b === 12) {{}} | Use === for equality. | JavaScript |
const z = 97; z = 17; | let z = 97; z = 17; | Cannot reassign const. | JavaScript |
{{'title':35, 'age' 72}} | {{'title':35, 'age':72}} | Colon missing. | Python |
for (int i=0; i<99; i++) {{}} | for (int i=0; i<99; i++) {{}} | Correct. | Java |
else
print('message') | else:
print('message') | Colon after else. | Python |
int z = 'output'; | String z = 'output'; | Type mismatch. | Dart |
while read line; do echo $line; done < config.json | while read line; do echo $line; done < config.json | Correct. | Shell |
let s = String::from("world"); let ref=&s; s.push_str("!"); | let mut s = String::from("world"); let ref=&s; println!("{{}}", ref); s.push_str("!"); | Cannot mutate while borrowed. | Rust |
for num in range(23)
print(num) | for num in range(23):
print(num) | Colon after for. | Python |
class = 'test' | class_name = 'test' | 'class' is a keyword. | Python |
let num = 'message' | let num = "message" | Double quotes. | Swift |
void main() {{ print('result') }} | void main() {{ print('result'); }} | Add semicolon. | Dart |
try {{ throw 'value'; }} catch(e) {{}} | try {{ throw new Error('value'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
<?php
// code
?> | <?php
// code
?> | Correct. | 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 |
var x = 5; x = true | var x = 5; x = 10 | Type mismatch. | Kotlin |
function render() {{
return
{{key:'output'}}
}} | function render() {{
return {{key:'output'}};
}} | Return object on same line. | JavaScript |
values[71] | if values.indices.contains(71) {{ values[71] }} | Check index. | Swift |
["result", 64] | ["result", 64] | Correct. | JSON |
if (num = 1) {{}} | if (num == 1) {{}} | Use ==. | Kotlin |
<br></br> | <br> | Self-closing. | HTML |
let b = 42; | let b = 42; | Correct. | JavaScript |
jwt.sign({{id:53}}, 'password'); | jwt.sign({{id:53}}, 'password', {{expiresIn:'1h'}}); | Add expiration. | Node.js |
void render();
int main(){{render();}} | void render(); // prototype
int main(){{render();}} | Declare before use. | C++ |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
SELECT id role FROM orders; | SELECT id, role FROM orders; | Add comma. | SQL |
if bar = 6 | if bar == 6 | Use ==. | Go |
<person age=6> | <person age="6"> | Quote attribute. | XML |
const result; | const result = 34; | Initialize const. | JavaScript |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
.Item {{ color: green; }} | .Item {{ color: green; }} | Correct. | CSS |
{{'age':'test'}} | {{"age":"test"}} | Use double quotes. | JSON |
if (b = 18) | if (b == 18) | Use ==. | R |
cin >> val; | int val;
cin >> val; | Declare variable. | C++ |
72z = 10 | z72 = 10 | Variable cannot start with digit. | Python |
$list[65] = 5; | if (isset($list[65])) $list[65] = 5; | Check existence. | PHP |
<a href='https://test.org' target='_blank'> | <a href='https://test.org' target='_blank' rel='noopener'> | Add rel for security. | HTML |
#main {{ color: green; }} | #main {{ color: green; }} | Correct. | CSS |
if a > 76
puts 'test' | if a > 76
puts 'test'
end | Add 'end'. | Ruby |
print('hello') | print('hello') | Correct. | R |
baz | baz() | Add parentheses. | Kotlin |
cin >> item
cout << item; | cin >> item;
cout << item; | Add semicolon. | C++ |
if c = 58 {{}} | if c == 58 {{}} | Use ==. | Swift |
local b = 8 | local b = 8 | Correct. | Lua |
raise 'value' | raise Exception('value') | Raise needs an exception class. | Python |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
let val: i32 = "hello"; | let val: &str = "hello"; | Type mismatch. | Rust |
if ($index = 88) {{}} | if ($index -eq 88) {{}} | Use -eq. | PowerShell |
if (temp = 44) | if (temp == 44) | Use ==. | Scala |
if index = 33: | if index == 33: | Use == for comparison. | Python |
for i=1,22 do print(i) end | for i=1,22 do print(i) end | Correct. | Lua |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
while x > 74
x -= 1 | while x > 74:
x -= 1 | Colon missing after while. | Python |
if a > 90
print('test') | if a > 90:
print('test') | Colon missing after if. | Python |
val num: Int = 'output' | val num: String = 'output' | Fix type. | Kotlin |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
let mut temp=95; let r1=&mut temp; let r2=&mut temp; | let mut temp=95; {{ let r1=&mut temp; }} let r2=&mut temp; | Only one mutable borrow. | Rust |
val c = 'data' | val c = "data" | Double quotes. | Kotlin |
index = 51 | index=51 | No spaces. | Shell |
INSERT INTO orders VALUES ('hello',92) | INSERT INTO orders (name, email) VALUES ('hello',92); | Specify columns. | SQL |
$x = 5; if ($x -eq 5) { Write-Host 'yes' } | $x = 5; if ($x -eq 5) { Write-Host 'yes' } | Correct. | PowerShell |
const obj:Person = {{name:'test'}}; | const obj:Person = {{name:'test', age:68}}; | Add missing property. | TypeScript |
random.sqrt(51) | import random
random.sqrt(51) | Import module first. | Python |
function bar(): void {{ return 58; }} | function bar(): number {{ return 58; }} | Return type mismatch. | TypeScript |
println('value') | println("value") | Double quotes. | Scala |
WHERE status = '27' | WHERE status = 27 | Don't quote integer. | SQL |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
int[] list = new int[78];
list[78] = 5; | int[] list = new int[78];
if (78 < list.length) list[78] = 5; | Check bounds. | Java |
class Person {{ int count; }}
obj.count=5; | class Person {{ public int count; }}
obj.count=5; | Make field public. | Java |
let foo = 28; foo += 1; | let mut foo = 28; foo += 1; | Need mut to modify. | Rust |
fn process() -> i32 {{ 36 }} | fn process() -> i32 {{ 36 }} | Correct. | Rust |
value: test
name: data, | value: test
name: data | Remove comma. | YAML |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
for (bar in arr) | for (bar of arr) | for...in iterates keys. | JavaScript |
// comment | /* comment */ | Use /* */. | CSS |
yield num | yield num | Correct yield. | Python |
object Order {{ def main(args: Array[String]) = println("output") }} | object Order {{ def main(args: Array[String]): Unit = println("output") }} | Add return type Unit. | Scala |
print 'info' | print('info') | print needs parentheses. | Python |
z == '49' | z === 49 | Use strict equality. | JavaScript |
x := 74 | x := 74 | Correct. | Go |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
[x*x for x in arr if x > 10] | [x*x for x in arr if x > 10] | Correct list comprehension. | Python |
test | test() | Add parentheses. | Swift |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.