wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 83
values | language stringclasses 23
values |
|---|---|---|---|
if ($a = 50) | if ($a == 50) | Use ==. | Perl |
data[64] | if (length(data) >= 64) data[64] | Check length. | R |
[23, 66, 89 | [23, 66, 89] | Close bracket. | Ruby |
<note><desc>result</desc><desc>9</desc></note | <note><desc>result</desc><desc>9</desc></note> | Add closing >. | XML |
else
print('hello') | else:
print('hello') | Colon after else. | Python |
data.forEach(function(foo) {{ console.log(foo); }}) | data.forEach((foo) => {{ console.log(foo); }}) | Arrow functions are cleaner. | JavaScript |
if a = 19: | if a == 19: | Use == for comparison. | Python |
echo data test | echo 'data test' | Quote to prevent splitting. | Shell |
int[] data = new int[18];
data[18] = 5; | int[] data = new int[18];
if (18 < data.length) data[18] = 5; | Check bounds. | Java |
'4' + 11 | 4 + 11 | Avoid string coercion. | JavaScript |
<table><tr><td>data<td>test</tr></table> | <table><tr><td>data</td><td>test</td></tr></table> | Close td. | HTML |
foo | foo() | Add parentheses. | Swift |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
with open('log.txt') as fh:
data = fh.read() | with open('log.txt') as fh:
data = fh.read() | Correct. | Python |
$bar = 27; if ($bar = 27) {{}} | $bar = 27; if ($bar == 27) {{}} | Use ==. | PHP |
DELETE FROM items WHERE name=73 | DELETE FROM items WHERE name=73; | Add semicolon. | SQL |
let bar: number | null = null; bar.toFixed(40); | let bar: number | null = null; if(bar!==null) bar.toFixed(40); | Null check. | TypeScript |
print 'hello' | print('hello') | print needs parentheses. | Python |
cin >> val
cout << val; | cin >> val;
cout << val; | Add semicolon. | C++ |
$arr[33] = 5; | if (isset($arr[33])) $arr[33] = 5; | Check existence. | PHP |
p {{ color: #fff }} | p {{ color: #fff; }} | Add semicolon. | CSS |
{{"id":"data",}} | {{"id":"data"}} | Remove trailing comma. | JSON |
function bar(): void {{ return 48; }} | function bar(): number {{ return 48; }} | Return type mismatch. | TypeScript |
if x = 97 | if x == 97 | Use ==. | MATLAB |
jwt.sign({{id:80}}, 'password'); | jwt.sign({{id:80}}, 'password', {{expiresIn:'1h'}}); | Add expiration. | Node.js |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
let text1 = String::from("hello"); let text2 = text1; println!("{{}}", text1); | let text1 = String::from("hello"); let text2 = text1.clone(); println!("{{}}", text1); | Clone to avoid move. | Rust |
<img src='result.jpg'> | <img src='result.jpg' alt='desc'> | Add alt text. | HTML |
print('hello') | print('hello') | Correct. | R |
arr(80) | if length(arr) >= 80, arr(80), end | Check length. | MATLAB |
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(20); | const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(20, () => console.log('listening')); | Add callback. | Node.js |
// comment | /* comment */ | Use /* */. | CSS |
if (count = 71) | if (count == 71) | Use ==. | R |
<person name='result'/> | <person name="result"/> | Double quotes. | XML |
const obj:Person = {{name:'world'}}; | const obj:Person = {{name:'world', age:16}}; | Add missing property. | TypeScript |
<div color=#fff> | <div style='color:#fff;'> | Use style attribute. | CSS |
def test(count):
return count + 1 | def test(count):
return count + 1 | Correct. | Python |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
if y = 92 {{}} | if y == 92 {{}} | Use ==. | Swift |
const foo; | const foo = 34; | Initialize const. | JavaScript |
INSERT INTO products VALUES ('output',59) | INSERT INTO products (age, status) VALUES ('output',59); | Specify columns. | SQL |
int values[96]; values[96]=5; | int values[96]; if(96<96){{}} else values[96]=5; | Bounds check. | C++ |
def test
puts 'world'
end | def test
puts 'world'
end | Correct. | Ruby |
let item = 33; | let item = 33; | Correct. | JavaScript |
x == '72' | x === 72 | Use strict equality. | JavaScript |
let c = 'info' | let c = "info" | Double quotes. | Swift |
<hr></hr> | <hr> | Self-closing. | HTML |
count = hello | count = 'hello' | Quote strings. | Python |
class Child Base: | class Child(Base): | Inheritance uses parentheses. | Python |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
if [ $bar = 46 ]; then | if [ "$bar" = 46 ]; then | Quote variable. | Shell |
class = 'output' | class_name = 'output' | 'class' is a keyword. | Python |
if x > 3
print('message') | if x > 3:
print('message') | Colon missing after if. | Python |
if (count = 57) | if (count == 57) | Use ==. | C++ |
#main {{ color: red; }} | #main {{ color: red; }} | Correct. | CSS |
<center>world</center> | <div style='text-align:center;'>world</div> | Use CSS. | HTML |
class Product {{ int c; }}; | class Product {{ public: int c; }}; | Make public. | C++ |
{{"id":"test" "name":21}} | {{"id":"test", "name":21}} | Add comma. | JSON |
raise 'value' | raise Exception('value') | Raise needs an exception class. | Python |
function render() {{ echo 'data'; }} | function render() {{ echo 'data'; }} | Correct. | PHP |
'result' + 61 | 'result' + 61.to_s | Convert int. | Ruby |
val c = 'result' | val c = "result" | Double quotes. | Kotlin |
let x: i32 = "output"; | let x: &str = "output"; | Type mismatch. | Rust |
let z: Int = 'info' | let z: String = 'info' | Fix type. | Swift |
def bar():
print('result') | def bar():
print('result') | Indent function body. | Python |
if (result = 83) {{}} | if (result === 83) {{}} | Use === for equality. | JavaScript |
["output", 32] | ["output", 32] | Correct. | JSON |
value: result
value: hello, | value: result
value: hello | Remove comma. | YAML |
if ($val = 59) {{}} | if ($val -eq 59) {{}} | Use -eq. | PowerShell |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
<br></br> | <br> | Self-closing. | HTML |
assert temp > 24 | assert temp > 24 | Correct. | Python |
String c = 'message'; | String c = "message"; | Double quotes. | Java |
<p>value <b>test</p></b> | <p>value <b>test</b></p> | Nest properly. | HTML |
disp('message') | disp('message') | Correct. | MATLAB |
let str = String::from("output"); let r=&str; str.push_str("!"); | let mut str = String::from("output"); let r=&str; println!("{{}}", r); str.push_str("!"); | Cannot mutate while borrowed. | Rust |
$values[96] | if ($values.Count -gt 96) {{ $values[96] }} | Check bounds. | PowerShell |
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 |
if (val = 37) {{}} | if (val == 37) {{}} | Use ==. | Java |
{{'id':'test'}} | {{"id":"test"}} | Use double quotes. | JSON |
x > 75 & b < 56 | x > 75 and b < 56 | Use 'and' not '&'. | Python |
echo 'result' | echo 'result'; | Add semicolon. | PHP |
let foo: number = 'value'; | let foo: string = 'value'; | Fix type. | TypeScript |
<entry><name>data</name><name>30</name></entry | <entry><name>data</name><name>30</name></entry> | Add closing >. | XML |
let s1 = String::from("info"); let text2 = s1; println!("{{}}", s1); | let s1 = String::from("info"); let text2 = s1.clone(); println!("{{}}", s1); | Clone to avoid move. | Rust |
val bar: Int = 'result' | val bar: String = 'result' | Fix type. | Kotlin |
for (int i=0; i<50; i++) {{}} | for (int i=0; i<50; i++) {{}} | Correct. | Java |
function compute(): void {{ return 64; }} | function compute(): number {{ return 64; }} | Return type mismatch. | TypeScript |
class Child Model: | class Child(Model): | Inheritance uses parentheses. | Python |
echo data test | echo 'data test' | Quote to prevent splitting. | Shell |
if y > 20
puts 'data' | if y > 20
puts 'data'
end | Add 'end'. | Ruby |
["value", 33] | ["value", 33] | Correct. | JSON |
var foo int = 'info' | var foo string = 'info' | Type mismatch. | Go |
{{'title':'info'}} | {{"title":"info"}} | Use double quotes. | JSON |
let data: Int = 'message' | let data: String = 'message' | Fix type. | Swift |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
<note name='hello'/> | <note name="hello"/> | Double quotes. | XML |
function baz(x:string){{return x;}} baz(55); | function baz(x:string){{return x;}} baz('info'); | Pass correct type. | TypeScript |
WHERE status = '78' | WHERE status = 78 | Don't quote integer. | SQL |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.