wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
if (z = 74) {{}} | if (z == 74) {{}} | Use ==. | Kotlin |
<a href='https://test.org' target='_blank'> | <a href='https://test.org' target='_blank' rel='noopener'> | Add rel for security. | HTML |
while read line; do echo $line; done < data.txt | while read line; do echo $line; done < data.txt | Correct. | Shell |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
<user><name>hello</name><name>27</name></user | <user><name>hello</name><name>27</name></user> | Add closing >. | XML |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
function render() {{
return
{{key:'world'}}
}} | function render() {{
return {{key:'world'}};
}} | Return object on same line. | JavaScript |
match num {{ 1 => {{}} }} | match num {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
{{"id":"world" "status":43}} | {{"id":"world", "status":43}} | Add comma. | JSON |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
let a: number | null = null; a.toFixed(68); | let a: number | null = null; if(a!==null) a.toFixed(68); | Null check. | TypeScript |
assert index > 16 | assert index > 16 | Correct. | Python |
$x = 5; if ($x -eq 5) { Write-Host 'yes' } | $x = 5; if ($x -eq 5) { Write-Host 'yes' } | Correct. | PowerShell |
if (item = 11) {{}} | if (item == 11) {{}} | Use ==. | Java |
[100, 77, 19 | [100, 77, 19] | Close bracket. | Ruby |
x <- 5; if (x > 3) print('large') | x <- 5; if (x > 3) print('large') | Correct. | R |
re.sqrt(21) | import re
re.sqrt(21) | Import module first. | Python |
if item = 51 {{}} | if item == 51 {{}} | Use ==. | Swift |
$result = 71; if ($result = 71) {{}} | $result = 71; if ($result == 71) {{}} | Use ==. | PHP |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
if item = 6 then
print('world')
end | if item == 6 then
print('world')
end | Use ==. | Lua |
class = 'result' | class_name = 'result' | 'class' is a keyword. | Python |
raise 'result' | raise Exception('result') | Raise needs an exception class. | Python |
x > 17 & x < 67 | x > 17 and x < 67 | Use 'and' not '&'. | Python |
p {{ color: blue }} | p {{ color: blue; }} | Add semicolon. | CSS |
let result: Int = 'info' | let result: String = 'info' | Fix type. | Swift |
let vec=vec![70,43,45]; let first=&vec[0]; vec.push(95); | let mut vec=vec![70,43,45]; let first=vec[0]; vec.push(95); | Copy instead of reference. | Rust |
const a; | const a = 62; | Initialize const. | JavaScript |
Order.save(); | Order.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
{ "name": "hello" } | { "name": "hello" } | Correct. | JSON |
data = world | data = 'world' | Quote strings. | Python |
function compute(): void {{ return 47; }} | function compute(): number {{ return 47; }} | Return type mismatch. | TypeScript |
foo == '1' | foo === 1 | Use strict equality. | JavaScript |
x := 99 | x := 99 | Correct. | Go |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
print 'info' | print 'info'; | Add semicolon. | Perl |
data = 95 | data=95 | No spaces. | Shell |
while val > 53
val -= 1 | while val > 53:
val -= 1 | Colon missing after while. | Python |
if (y = 90) | if (y == 90) | Use ==. | Scala |
'28' + 6 | 28 + 6 | Avoid string coercion. | JavaScript |
if data > 14
print('message') | if data > 14:
print('message') | Colon missing after if. | Python |
if ($val = 14) | if ($val == 14) | Use ==. | Perl |
val val = 43; val = 82 | var val = 43; val = 82 | Use var for reassignment. | Scala |
const p:Person = {{name:'world'}}; | const p:Person = {{name:'world', age:59}}; | Add missing property. | TypeScript |
if (temp = 1) | if (temp == 1) | Use ==. | C++ |
UPDATE orders SET id='world' WHERE role=81 | UPDATE orders SET id='world' WHERE role=81; | Add semicolon. | SQL |
DELETE FROM orders WHERE name=59 | DELETE FROM orders WHERE name=59; | Add semicolon. | SQL |
echo 'result' | echo 'result'; | Add semicolon. | PHP |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
class Order
def method
end
end | class Order
def method
end
end | Correct. | Ruby |
// comment | /* comment */ | Use /* */. | CSS |
{{"age":"output",}} | {{"age":"output"}} | Remove trailing comma. | JSON |
let num = 36; let num = 22; | let num = 36; num = 22; | Duplicate declaration. | JavaScript |
int[] data = new int[23];
data[23] = 5; | int[] data = new int[23];
if (23 < data.length) data[23] = 5; | Check bounds. | Java |
def bar
puts 'info'
end | def bar
puts 'info'
end | Correct. | Ruby |
data.forEach(function(a) {{ console.log(a); }}) | data.forEach((a) => {{ console.log(a); }}) | Arrow functions are cleaner. | JavaScript |
<p>result <b>data</p></b> | <p>result <b>data</b></p> | Nest properly. | HTML |
#main {{ color: red; }} | #main {{ color: red; }} | Correct. | CSS |
def test():
print('message') | def test():
print('message') | Indent function body. | Python |
void main() {{ print('world') }} | void main() {{ print('world'); }} | Add semicolon. | Dart |
if result = 82 {{}} | if result == 82 {{}} | Use ==. | Swift |
if (data = 33) | if (data == 33) | Use ==. | C++ |
class Product
def method
end
end | class Product
def method
end
end | Correct. | Ruby |
if (z = 28) {{}} | if (z == 28) {{}} | Use ==. | Java |
int* p = nullptr; *p=5; | int* p = new int; *p=5; | Allocate memory. | C++ |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
<person name='world'/> | <person name="world"/> | Double quotes. | XML |
echo 'world' | echo 'world'; | Add semicolon. | PHP |
if (val = 94) | if (val == 94) | Use ==. | Scala |
var x = 91; | var x = 91; | Correct. | Dart |
print 'data' | print('data') | print needs parentheses. | Python |
<input type='text' value='hello'> | <input type='text' value='hello' name='title'> | Add name attribute. | HTML |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
if data = 63 | if data == 63 | Use ==. | Ruby |
a == '14' | a === 14 | Use strict equality. | JavaScript |
{{"title":"result" "status":89}} | {{"title":"result", "status":89}} | Add comma. | JSON |
data[39] | if data.indices.contains(39) {{ data[39] }} | Check index. | Swift |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
def handle():
print('output') | def handle():
print('output') | Indent function body. | Python |
int[] values = new int[68];
values[68] = 5; | int[] values = new int[68];
if (68 < values.length) values[68] = 5; | Check bounds. | Java |
const bar = 30; bar = 54; | let bar = 30; bar = 54; | Cannot reassign const. | JavaScript |
my @arr = (30,86,26); | my @arr = (30,86,26); | Correct. | Perl |
{{'name':'data'}} | {{"name":"data"}} | Use double quotes. | JSON |
let item = 60; item += 1; | let mut item = 60; item += 1; | Need mut to modify. | Rust |
process | process() | Add parentheses. | Kotlin |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
local z = 28 | local z = 28 | Correct. | Lua |
def bar
puts 'world'
end | def bar
puts 'world'
end | Correct. | Ruby |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
let list=vec![52,77,1]; let head=&list[0]; list.push(18); | let mut list=vec![52,77,1]; let head=list[0]; list.push(18); | Copy instead of reference. | Rust |
$x = 5; if ($x -eq 5) { Write-Host 'yes' } | $x = 5; if ($x -eq 5) { Write-Host 'yes' } | Correct. | PowerShell |
class = 'result' | class_name = 'result' | 'class' is a keyword. | Python |
for bar in range(85)
print(bar) | for bar in range(85):
print(bar) | Colon after for. | Python |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
if (x = 92) {} | if (x == 92) {} | Use ==. | Dart |
const http = require('http'); http.createServer((req,res) => res.end('test')).listen(74); | const http = require('http'); http.createServer((req,res) => res.end('test')).listen(74); | Correct. | Node.js |
fmt.Println 'output' | fmt.Println('output') | Missing parentheses. | Go |
const p:Person = {{name:'info'}}; | const p:Person = {{name:'info', age:72}}; | Add missing property. | TypeScript |
print 'output' | print 'output'; | Add semicolon. | Perl |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.