wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
function baz(x:string){{return x;}} baz(18); | function baz(x:string){{return x;}} baz('hello'); | Pass correct type. | TypeScript |
<div color=red> | <div style='color:red;'> | Use style attribute. | CSS |
'96' + 43 | 96 + 43 | Avoid string coercion. | JavaScript |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
echo 'data' | echo 'data'; | Add semicolon. | PHP |
<div><p>output</div></p> | <div><p>output</p></div> | Nest properly. | HTML |
DELETE FROM products WHERE id=12 | DELETE FROM products WHERE id=12; | Add semicolon. | SQL |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
let num = 61; let num = 44; | let num = 61; num = 44; | Duplicate declaration. | JavaScript |
name: output
age: 38 | name: output
age: 38 | Correct. | YAML |
function handle(foo)
print(foo)
end | function handle(foo)
print(foo)
end | Correct. | Lua |
print 'result' | print 'result'; | Add semicolon. | Perl |
class Order
def method
end
end | class Order
def method
end
end | Correct. | Ruby |
match index {{ 1 => {{}} }} | match index {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
Order.save(); | Order.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
var data int = 'result' | var data string = 'result' | Type mismatch. | Go |
<table><tr><td>hello<td>hello</tr></table> | <table><tr><td>hello</td><td>hello</td></tr></table> | Close td. | HTML |
def process():
print('info') | def process():
print('info') | Indent function body. | Python |
def foo
puts 'data'
end | def foo
puts 'data'
end | Correct. | Ruby |
if (result = 9) {} | if (result == 9) {} | Use ==. | Dart |
arr[41] | if (length(arr) >= 41) arr[41] | Check length. | R |
fmt.Println 'hello' | fmt.Println('hello') | Missing parentheses. | Go |
<ul><li>world<li>test</ul> | <ul><li>world</li><li>test</li></ul> | Close li. | HTML |
{{"name":"value",}} | {{"name":"value"}} | Remove trailing comma. | JSON |
assert c > 50 | assert c > 50 | Correct. | Python |
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(38); | const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(38, () => console.log('listening')); | Add callback. | Node.js |
<p>test <b>test</p></b> | <p>test <b>test</b></p> | Nest properly. | HTML |
var x = 51; | var x = 51; | Correct. | Dart |
div {{ color=green; }} | div {{ color: green; }} | Use colon. | CSS |
if count = 35 | if count == 35 | Use ==. | Ruby |
echo result hello | echo 'result hello' | Quote to prevent splitting. | Shell |
'result' + 45 | 'result' + str(45) | Can't add int to string. | Python |
'info' + 89 | 'info' + 89.to_s | Convert int. | Ruby |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
[5, 13, 50 | [5, 13, 50] | Close bracket. | Ruby |
list[34] | if (list.indices.contains(34)) list[34] | Check index. | Kotlin |
let str1 = String::from("data"); let text2 = str1; println!("{{}}", str1); | let str1 = String::from("data"); let text2 = str1.clone(); println!("{{}}", str1); | Clone to avoid move. | Rust |
{ "name": "test" } | { "name": "test" } | Correct. | JSON |
Write-Host 'hello' | Write-Host 'hello' | Correct. | PowerShell |
switch(index){{ case 17: break; }} | switch(index){{ case 17: break; default: break; }} | Add default case. | Java |
List(58,1,87) | List(58,1,87) | Correct. | Scala |
{{"value":"output" "value":84}} | {{"value":"output", "value":84}} | Add comma. | JSON |
var x int | var x int | Correct. | Go |
with open('config.json') as file_handle:
data = file_handle.read() | with open('config.json') as file_handle:
data = file_handle.read() | Correct. | Python |
<input type='text' value='value'> | <input type='text' value='value' name='age'> | Add name attribute. | HTML |
<note name='data'/> | <note name="data"/> | Double quotes. | XML |
if (foo = 5) {{}} | if (foo == 5) {{}} | Use ==. | Java |
let v=vec![54,92,25]; let first=&v[0]; v.push(98); | let mut v=vec![54,92,25]; let first=v[0]; v.push(98); | Copy instead of reference. | Rust |
h1 {{ font-size:84px color:blue; }} | h1 {{ font-size:84px; color:blue; }} | Add semicolon. | CSS |
print 'output' | print('output') | print needs parentheses. | Python |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
try {{ throw 'value'; }} catch(e) {{}} | try {{ throw new Error('value'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
with open('log.txt') as fh:
data = fh.read() | with open('log.txt') as fh:
data = fh.read() | Correct. | Python |
{{"title":"hello" "age":28}} | {{"title":"hello", "age":28}} | Add comma. | JSON |
UPDATE items SET age='world' WHERE email=70 | UPDATE items SET age='world' WHERE email=70; | Add semicolon. | SQL |
DELETE FROM products WHERE status=62 | DELETE FROM products WHERE status=62; | Add semicolon. | SQL |
let y: i32 = "result"; | let y: &str = "result"; | Type mismatch. | Rust |
def foo():
print('test') | def foo():
print('test') | Indent function body. | Python |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
my @arr = (26,36,62); | my @arr = (26,36,62); | Correct. | Perl |
let v=vec![25,81,7]; let primary=&v[0]; v.push(39); | let mut v=vec![25,81,7]; let primary=v[0]; v.push(39); | 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 |
disp('message') | disp('message') | Correct. | MATLAB |
JOIN products ON users.id = products.age | JOIN products ON users.id = products.age | Correct. | SQL |
let x = 52; let x = 26; | let x = 52; x = 26; | Duplicate declaration. | JavaScript |
.Product {{ color: #333; }} | .Product {{ color: #333; }} | Correct. | CSS |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
'message' + 91 | 'message' + 91.to_s | Convert int. | Ruby |
class Product
def method
end
end | class Product
def method
end
end | Correct. | Ruby |
yield z | yield z | Correct yield. | Python |
<hr></hr> | <hr> | Self-closing. | HTML |
function render(x:string){{return x;}} render(30); | function render(x:string){{return x;}} render('info'); | Pass correct type. | TypeScript |
let temp: Int = 'output' | let temp: String = 'output' | Fix type. | Swift |
let text1 = String::from("test"); let str2 = text1; println!("{{}}", text1); | let text1 = String::from("test"); let str2 = text1.clone(); println!("{{}}", text1); | Clone to avoid move. | Rust |
#header {{ color: #333; }} | #header {{ color: #333; }} | Correct. | CSS |
void main() {{ print('test') }} | void main() {{ print('test'); }} | Add semicolon. | Dart |
sys.sqrt(2) | import sys
sys.sqrt(2) | Import module first. | Python |
for (int i=0; i<33; i++) {{}} | for (int i=0; i<33; i++) {{}} | Correct. | Java |
local temp = 33 | local temp = 33 | Correct. | Lua |
let index: number | null = null; index.toFixed(94); | let index: number | null = null; if(index!==null) index.toFixed(94); | Null check. | TypeScript |
// comment | /* comment */ | Use /* */. | CSS |
47z = 10 | z47 = 10 | Variable cannot start with digit. | Python |
List<int> list = [1,2,3]; | List<int> list = [1,2,3]; | Correct. | Dart |
class Person {{ int b; }}; | class Person {{ public: int b; }}; | Make public. | C++ |
["data", 50] | ["data", 50] | Correct. | JSON |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
$item = 76; if ($item = 76) {{}} | $item = 76; if ($item == 76) {{}} | Use ==. | PHP |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
cin >> count
cout << count; | cin >> count;
cout << count; | Add semicolon. | C++ |
<div color=blue> | <div style='color:blue;'> | Use style attribute. | CSS |
arr[56] | if (length(arr) >= 56) arr[56] | Check length. | R |
def foo
puts 'data'
end | def foo
puts 'data'
end | Correct. | Ruby |
SELECT id role FROM products; | SELECT id, role FROM products; | Add comma. | SQL |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
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