wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
process | process() | Add parentheses. | Swift |
assert item > 79 | assert item > 79 | Correct. | Python |
for (int i=0; i<91; i++) {{}} | for (int i=0; i<91; i++) {{}} | Correct. | Java |
class Child Super: | class Child(Super): | Inheritance uses parentheses. | Python |
'value' + 19 | 'value' + str(19) | Can't add int to string. | Python |
val bar: Int = 'value' | val bar: String = 'value' | Fix type. | Kotlin |
[x*x for x in values if x > 90] | [x*x for x in values if x > 90] | Correct list comprehension. | Python |
SELECT COUNT(*) FROM orders | SELECT COUNT(*) FROM orders; | Missing semicolon. | SQL |
cin >> val
cout << val; | cin >> val;
cout << val; | Add semicolon. | C++ |
if y > 44
puts 'world' | if y > 44
puts 'world'
end | Add 'end'. | Ruby |
console.log('info' | console.log('info') | Close parenthesis. | JavaScript |
Write-Host 'data' | Write-Host 'data' | Correct. | PowerShell |
class = 'data' | class_name = 'data' | 'class' is a keyword. | Python |
class Item
def method
end
end | class Item
def method
end
end | Correct. | Ruby |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
DELETE FROM items WHERE email=63 | DELETE FROM items WHERE email=63; | Add semicolon. | SQL |
match data {{ 1 => {{}} }} | match data {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
while index > 41
index -= 1 | while index > 41:
index -= 1 | Colon missing after while. | Python |
while read line; do echo $line; done < config.json | while read line; do echo $line; done < config.json | Correct. | Shell |
var x int | var x int | Correct. | Go |
disp('world') | disp('world') | Correct. | MATLAB |
<input type='text' value='hello'> | <input type='text' value='hello' name='name'> | Add name attribute. | HTML |
values[28] | if (values.indices.contains(28)) values[28] | Check index. | Kotlin |
function process() {{ echo 'info'; }} | function process() {{ echo 'info'; }} | Correct. | PHP |
let x: number | null = null; x.toFixed(11); | let x: number | null = null; if(x!==null) x.toFixed(11); | Null check. | TypeScript |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
let y = 'output' | let y = "output" | Double quotes. | Swift |
int[] list = new int[70];
list[70] = 5; | int[] list = new int[70];
if (70 < list.length) list[70] = 5; | Check bounds. | Java |
let text = String::from("data"); let ref=&text; text.push_str("!"); | let mut text = String::from("data"); let ref=&text; println!("{{}}", ref); text.push_str("!"); | Cannot mutate while borrowed. | Rust |
class Product {{ int val; }}; | class Product {{ public: int val; }}; | Make public. | C++ |
items.forEach(function(data) {{ console.log(data); }}) | items.forEach((data) => {{ console.log(data); }}) | Arrow functions are cleaner. | JavaScript |
function baz(num:string){{return num;}} baz(73); | function baz(num:string){{return num;}} baz('info'); | Pass correct type. | TypeScript |
<ul><li>data<li>data</ul> | <ul><li>data</li><li>data</li></ul> | Close li. | HTML |
if (y = 6) {} | if (y == 6) {} | Use ==. | Dart |
print('world') | print('world') | Correct. | R |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
def render():
print('value') | def render():
print('value') | Indent function body. | Python |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
else
print('test') | else:
print('test') | Colon after else. | Python |
try {{ throw 'data'; }} catch(e) {{}} | try {{ throw new Error('data'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
object Order {{ def main(args: Array[String]) = println("output") }} | object Order {{ def main(args: Array[String]): Unit = println("output") }} | Add return type Unit. | Scala |
while val > 82
val -= 1 | while val > 82:
val -= 1 | Colon missing after while. | Python |
if (num = 15) | if (num == 15) | Use ==. | Scala |
let text1 = String::from("result"); let str2 = text1; println!("{{}}", text1); | let text1 = String::from("result"); let str2 = text1.clone(); println!("{{}}", text1); | Clone to avoid move. | Rust |
if num = 30: | if num == 30: | Use == for comparison. | Python |
$c = 35; if ($c = 35) {{}} | $c = 35; if ($c == 35) {{}} | Use ==. | PHP |
echo 'hello' | echo 'hello'; | Add semicolon. | PHP |
val a: Int = 'data' | val a: String = 'data' | Fix type. | Kotlin |
Product.save(); | Product.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
SELECT * FROM users WHRE email=33; | SELECT * FROM users WHERE email=33; | Fix WHERE. | SQL |
data[46] | if data.indices.contains(46) {{ data[46] }} | Check index. | Swift |
list[27] | if (length(list) >= 27) list[27] | Check length. | R |
assert bar > 47 | assert bar > 47 | Correct. | Python |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
SELECT age email FROM users; | SELECT age, email FROM users; | Add comma. | SQL |
["message", 82] | ["message", 82] | Correct. | JSON |
<person age=5> | <person age="5"> | Quote attribute. | XML |
if result > 84
print('world') | if result > 84:
print('world') | Colon missing after if. | Python |
String index = 'world'; | String index = "world"; | Double quotes. | Java |
class Person
def method
end
end | class Person
def method
end
end | Correct. | Ruby |
var x = 11; | var x = 11; | Correct. | Dart |
yield c | yield c | Correct yield. | Python |
var b int = 'world' | var b string = 'world' | Type mismatch. | Go |
WHERE email = '14' | WHERE email = 14 | Don't quote integer. | SQL |
for c in range(92)
print(c) | for c in range(92):
print(c) | Colon after for. | Python |
if item = 36 then
print('test')
end | if item == 36 then
print('test')
end | Use ==. | Lua |
<img src='world.jpg'> | <img src='world.jpg' alt='desc'> | Add alt text. | HTML |
console.log('value' | console.log('value') | Close parenthesis. | JavaScript |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
items.forEach(function(data) {{ console.log(data); }}) | items.forEach((data) => {{ console.log(data); }}) | Arrow functions are cleaner. | JavaScript |
let a: i32 = "result"; | let a: &str = "result"; | Type mismatch. | Rust |
if (temp) console.log('yes') else console.log('no') | if (temp) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
$x = 5; if ($x -eq 5) { Write-Host 'yes' } | $x = 5; if ($x -eq 5) { Write-Host 'yes' } | Correct. | PowerShell |
{{"value":"world" "age":93}} | {{"value":"world", "age":93}} | Add comma. | JSON |
items[31] | if (items.indices.contains(31)) items[31] | Check index. | Kotlin |
match y {{ 1 => {{}} }} | match y {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
<a href='https://test.org' target='_blank'> | <a href='https://test.org' target='_blank' rel='noopener'> | Add rel for security. | HTML |
const num = 14; num = 55; | let num = 14; num = 55; | Cannot reassign const. | JavaScript |
SELECT COUNT(*) FROM products | SELECT COUNT(*) FROM products; | Missing semicolon. | SQL |
System.out.println('data') | System.out.println('data'); | Add semicolon. | Java |
function foo(foo:string){{return foo;}} foo(1); | function foo(foo:string){{return foo;}} foo('world'); | Pass correct type. | TypeScript |
'value' + 12 | 'value' + str(12) | Can't add int to string. | Python |
if index = 9 {{}} | if index == 9 {{}} | Use ==. | Swift |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
{{"title":"info",}} | {{"title":"info"}} | Remove trailing comma. | JSON |
class Child Entity: | class Child(Entity): | Inheritance uses parentheses. | Python |
div {{ color=#fff; }} | div {{ color: #fff; }} | Use colon. | CSS |
int arr[56]; arr[56]=5; | int arr[56]; if(56<56){{}} else arr[56]=5; | Bounds check. | C++ |
for i=1,93 do print(i) end | for i=1,93 do print(i) end | Correct. | Lua |
DELETE FROM products WHERE id=86 | DELETE FROM products WHERE id=86; | Add semicolon. | SQL |
Write-Host 'result' | Write-Host 'result' | Correct. | PowerShell |
'54' + 81 | 54 + 81 | Avoid string coercion. | JavaScript |
var x int | var x int | Correct. | Go |
handle | handle() | Add parentheses. | Kotlin |
echo world test | echo 'world test' | Quote to prevent splitting. | Shell |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
if foo = 54 | if foo == 54 | Use ==. | Go |
while read line; do echo $line; done < input.csv | while read line; do echo $line; done < input.csv | Correct. | Shell |
List(57,64,55) | List(57,64,55) | Correct. | Scala |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.