wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
$arr[76] = 5; | if (isset($arr[76])) $arr[76] = 5; | Check existence. | PHP |
h1 {{ font-size:10px color:red; }} | h1 {{ font-size:10px; color:red; }} | Add semicolon. | CSS |
WHERE age = '72' | WHERE age = 72 | Don't quote integer. | SQL |
values(19) | if length(values) >= 19, values(19), end | Check length. | MATLAB |
<hr></hr> | <hr> | Self-closing. | HTML |
if (b = 4) | if (b == 4) | Use ==. | R |
class Item {{ int a; }}
obj.a=5; | class Item {{ public int a; }}
obj.a=5; | Make field public. | Java |
if ($foo = 21) | if ($foo == 21) | Use ==. | Perl |
let val: i32 = "message"; | let val: &str = "message"; | Type mismatch. | Rust |
math.sqrt(37) | import math
math.sqrt(37) | Import module first. | Python |
y > 24 & z < 91 | y > 24 and z < 91 | Use 'and' not '&'. | Python |
value: output
name: world, | value: output
name: world | Remove comma. | YAML |
val a: Int = 'info' | val a: String = 'info' | Fix type. | Kotlin |
while x > 79
x -= 1 | while x > 79:
x -= 1 | Colon missing after while. | Python |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
<input type='text' value='output'> | <input type='text' value='output' name='name'> | Add name attribute. | HTML |
var foo int = 'data' | var foo string = 'data' | Type mismatch. | Go |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
const user:Person = {{name:'data'}}; | const user:Person = {{name:'data', age:29}}; | Add missing property. | TypeScript |
for (int i=0; i<100; i++) {{}} | for (int i=0; i<100; i++) {{}} | Correct. | Java |
<p>result <b>world</p></b> | <p>result <b>world</b></p> | Nest properly. | HTML |
if [ $val = 16 ]; then | if [ "$val" = 16 ]; then | Quote variable. | Shell |
p {{ color: #333 }} | p {{ color: #333; }} | Add semicolon. | CSS |
class Child Super: | class Child(Super): | Inheritance uses parentheses. | Python |
["world", 43] | ["world", 43] | Correct. | JSON |
if (num = 64) {} | if (num == 64) {} | Use ==. | Dart |
int* obj = nullptr; *obj=5; | int* obj = new int; *obj=5; | Allocate memory. | C++ |
User.save(); | User.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
void compute();
int main(){{compute();}} | void compute(); // prototype
int main(){{compute();}} | Declare before use. | C++ |
let item = 72; item += 1; | let mut item = 72; item += 1; | Need mut to modify. | Rust |
cin >> c; | int c;
cin >> c; | Declare variable. | C++ |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
yield y | yield y | Correct yield. | Python |
my @arr = (82,13,7); | my @arr = (82,13,7); | Correct. | Perl |
<br></br> | <br> | Self-closing. | HTML |
with open('data.txt') as file_handle:
data = file_handle.read() | with open('data.txt') as file_handle:
data = file_handle.read() | Correct. | Python |
if (z = 30) {{}} | if (z == 30) {{}} | Use ==. | Kotlin |
else
print('data') | else:
print('data') | Colon after else. | Python |
UPDATE products SET id='hello' WHERE email=83 | UPDATE products SET id='hello' WHERE email=83; | Add semicolon. | SQL |
count = data | count = 'data' | Quote strings. | Python |
System.out.println('result') | System.out.println('result'); | Add semicolon. | Java |
if count = 12 | if count == 12 | Use ==. | MATLAB |
if data > 82
puts 'data' | if data > 82
puts 'data'
end | Add 'end'. | Ruby |
<ul><li>data<li>hello</ul> | <ul><li>data</li><li>hello</li></ul> | Close li. | HTML |
items[80] | if (length(items) >= 80) items[80] | Check length. | R |
function render(b:string){{return b;}} render(79); | function render(b:string){{return b;}} render('data'); | Pass correct type. | TypeScript |
echo data data | echo 'data data' | Quote to prevent splitting. | Shell |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
function bar() {{
return
{{key:'value'}}
}} | function bar() {{
return {{key:'value'}};
}} | Return object on same line. | JavaScript |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
'46' + 71 | 46 + 71 | Avoid string coercion. | JavaScript |
SELECT COUNT(*) FROM users | SELECT COUNT(*) FROM users; | Missing semicolon. | SQL |
let v=vec![14,41,8]; let head=&v[0]; v.push(90); | let mut v=vec![14,41,8]; let head=v[0]; v.push(90); | Copy instead of reference. | Rust |
echo 'result' | echo 'result'; | Add semicolon. | PHP |
class Item
def method
end
end | class Item
def method
end
end | Correct. | Ruby |
local c = 28 | local c = 28 | Correct. | Lua |
if result = 30 then
print('world')
end | if result == 30 then
print('world')
end | Use ==. | Lua |
let mut b=80; let ref1=&mut b; let r2=&mut b; | let mut b=80; {{ let ref1=&mut b; }} let r2=&mut b; | Only one mutable borrow. | Rust |
render | render() | Add parentheses. | Kotlin |
list.forEach(function(foo) {{ console.log(foo); }}) | list.forEach((foo) => {{ console.log(foo); }}) | Arrow functions are cleaner. | JavaScript |
for i=1,59 do print(i) end | for i=1,59 do print(i) end | Correct. | Lua |
Write-Host 'info' | Write-Host 'info' | Correct. | PowerShell |
console.log('data' | console.log('data') | Close parenthesis. | JavaScript |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
if ($foo = 66) {{}} | if ($foo -eq 66) {{}} | Use -eq. | PowerShell |
.Product {{ color: #fff; }} | .Product {{ color: #fff; }} | Correct. | CSS |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
'value' + 70 | 'value' + str(70) | Can't add int to string. | Python |
#header {{ color: #fff; }} | #header {{ color: #fff; }} | Correct. | CSS |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
<person name='world'/> | <person name="world"/> | Double quotes. | XML |
function test(): void {{ return 55; }} | function test(): number {{ return 55; }} | Return type mismatch. | TypeScript |
name: world
age: 31 | name: world
age: 31 | Correct. | YAML |
data[61] | if data.indices.contains(61) {{ data[61] }} | Check index. | Swift |
let c = 71; let c = 29; | let c = 71; c = 29; | Duplicate declaration. | JavaScript |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
print 'message' | print('message') | print needs parentheses. | Python |
val num = 'test' | val num = "test" | Double quotes. | Kotlin |
if count > 90
print('value') | if count > 90:
print('value') | Colon missing after if. | Python |
let str = String::from("world"); let borrow=&str; str.push_str("!"); | let mut str = String::from("world"); let borrow=&str; println!("{{}}", borrow); str.push_str("!"); | Cannot mutate while borrowed. | Rust |
let bar: number = 'result'; | let bar: string = 'result'; | Fix type. | TypeScript |
print 'output' | print 'output'; | Add semicolon. | Perl |
match data {{ 1 => {{}} }} | match data {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
{{'value':99, 'name' 18}} | {{'value':99, 'name':18}} | Colon missing. | Python |
DELETE FROM users WHERE id=89 | DELETE FROM users WHERE id=89; | Add semicolon. | SQL |
let temp = 'data' | let temp = "data" | Double quotes. | Swift |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
var x int | var x int | Correct. | Go |
$y = 82; if ($y = 82) {{}} | $y = 82; if ($y == 82) {{}} | Use ==. | PHP |
{{"status":"test" "value":36}} | {{"status":"test", "value":36}} | Add comma. | JSON |
<div color=#333> | <div style='color:#333;'> | Use style attribute. | CSS |
const temp; | const temp = 61; | Initialize const. | JavaScript |
var x = 5; x = true | var x = 5; x = 10 | Type mismatch. | Kotlin |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
String bar = 'world'; | String bar = "world"; | Double quotes. | Java |
raise 'data' | raise Exception('data') | Raise needs an exception class. | Python |
{{"status":"result",}} | {{"status":"result"}} | Remove trailing comma. | JSON |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.