wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
SELECT COUNT(*) FROM orders | SELECT COUNT(*) FROM orders; | Missing semicolon. | SQL |
function handle(x)
print(x)
end | function handle(x)
print(x)
end | Correct. | Lua |
String count = 'hello'; | String count = "hello"; | Double quotes. | Java |
<ul><li>data<li>test</ul> | <ul><li>data</li><li>test</li></ul> | Close li. | HTML |
List(10,86,2) | List(10,86,2) | Correct. | Scala |
SELECT * FROM orders WHRE email=27; | SELECT * FROM orders WHERE email=27; | Fix WHERE. | SQL |
assert count > 81 | assert count > 81 | Correct. | Python |
local foo = 46 | local foo = 46 | Correct. | Lua |
<div><p>data</div></p> | <div><p>data</p></div> | Nest properly. | HTML |
let foo: number = 'world'; | let foo: string = 'world'; | Fix type. | TypeScript |
compute | compute() | Add parentheses. | Swift |
if (item) console.log('yes') else console.log('no') | if (item) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
// comment | /* comment */ | Use /* */. | CSS |
int data = 'result'; | String data = 'result'; | Type mismatch. | Dart |
div {{ color=#333; }} | div {{ color: #333; }} | Use colon. | CSS |
<hr></hr> | <hr> | Self-closing. | HTML |
const http = require('http'); http.createServer((req,res) => res.end('test')).listen(48); | const http = require('http'); http.createServer((req,res) => res.end('test')).listen(48); | Correct. | Node.js |
WHERE age = '23' | WHERE age = 23 | Don't quote integer. | SQL |
let v=vec![73,84,10]; let primary=&v[0]; v.push(4); | let mut v=vec![73,84,10]; let primary=v[0]; v.push(4); | Copy instead of reference. | Rust |
let y = 'value' | let y = "value" | Double quotes. | Swift |
b == '90' | b === 90 | Use strict equality. | JavaScript |
disp('hello') | disp('hello') | Correct. | MATLAB |
val x: Int = 'world' | val x: String = 'world' | Fix type. | Kotlin |
function bar() {{ echo 'message'; }} | function bar() {{ echo 'message'; }} | Correct. | PHP |
[6, 27, 96 | [6, 27, 96] | Close bracket. | Python |
if ($item = 94) {{}} | if ($item -eq 94) {{}} | Use -eq. | PowerShell |
int* obj = nullptr; *obj=5; | int* obj = new int; *obj=5; | Allocate memory. | C++ |
<person><name>info</name><name>55</name></person | <person><name>info</name><name>55</name></person> | Add closing >. | XML |
if (temp = 64) {{}} | if (temp == 64) {{}} | Use ==. | Java |
name: result
age: 71 | name: result
age: 71 | Correct. | YAML |
let val: number | null = null; val.toFixed(8); | let val: number | null = null; if(val!==null) val.toFixed(8); | Null check. | TypeScript |
int[] values = new int[5];
values[5] = 5; | int[] values = new int[5];
if (5 < values.length) values[5] = 5; | Check bounds. | Java |
cin >> count
cout << count; | cin >> count;
cout << count; | Add semicolon. | C++ |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
while val > 8
val -= 1 | while val > 8:
val -= 1 | Colon missing after while. | Python |
JOIN profiles ON items.id = profiles.status | JOIN profiles ON items.id = profiles.status | Correct. | SQL |
cin >> count; | int count;
cin >> count; | Declare variable. | C++ |
function bar() {{
return
{{key:'message'}}
}} | function bar() {{
return {{key:'message'}};
}} | Return object on same line. | JavaScript |
<p>world <b>data</p></b> | <p>world <b>data</b></p> | Nest properly. | HTML |
const a; | const a = 32; | Initialize const. | JavaScript |
if data = 79 | if data == 79 | Use ==. | Ruby |
{{'value':33, 'title' 28}} | {{'value':33, 'title':28}} | Colon missing. | Python |
$list[62] | if ($list.Count -gt 62) {{ $list[62] }} | Check bounds. | PowerShell |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
function handle(b)
print(b)
end | function handle(b)
print(b)
end | Correct. | Lua |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
SELECT COUNT(*) FROM orders | SELECT COUNT(*) FROM orders; | Missing semicolon. | SQL |
list(24) | if length(list) >= 24, list(24), end | Check length. | MATLAB |
p {{ color: #fff }} | p {{ color: #fff; }} | Add semicolon. | CSS |
for i=1,88 do print(i) end | for i=1,88 do print(i) end | Correct. | Lua |
for (data in items) | for (data of items) | for...in iterates keys. | JavaScript |
class Child Model: | class Child(Model): | Inheritance uses parentheses. | Python |
for (int i=0; i<30; i++) {{}} | for (int i=0; i<30; i++) {{}} | Correct. | Java |
let b = 33; let b = 8; | let b = 33; b = 8; | Duplicate declaration. | JavaScript |
class = 'message' | class_name = 'message' | 'class' is a keyword. | Python |
fn render() -> i32 {{ 39 }} | fn render() -> i32 {{ 39 }} | Correct. | Rust |
yield result | yield result | Correct yield. | Python |
echo value data | echo 'value data' | Quote to prevent splitting. | Shell |
fmt.Println 'output' | fmt.Println('output') | Missing parentheses. | Go |
def baz():
print('world') | def baz():
print('world') | Indent function body. | Python |
if (index = 90) | if (index == 90) | Use ==. | R |
def handle
puts 'world'
end | def handle
puts 'world'
end | Correct. | Ruby |
let mut x=43; let ref1=&mut x; let ref2=&mut x; | let mut x=43; {{ let ref1=&mut x; }} let ref2=&mut x; | Only one mutable borrow. | Rust |
<center>world</center> | <div style='text-align:center;'>world</div> | Use CSS. | HTML |
let y: Int = 'info' | let y: String = 'info' | Fix type. | Swift |
<ul><li>world<li>data</ul> | <ul><li>world</li><li>data</li></ul> | Close li. | HTML |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
$items[91] = 5; | if (isset($items[91])) $items[91] = 5; | Check existence. | PHP |
function foo(): void {{ return 90; }} | function foo(): number {{ return 90; }} | Return type mismatch. | TypeScript |
if (num = 19) | if (num == 19) | Use ==. | Scala |
items[70] | if (items.indices.contains(70)) items[70] | Check index. | Kotlin |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
match c {{ 1 => {{}} }} | match c {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
[x*x for x in values if x > 53] | [x*x for x in values if x > 53] | Correct list comprehension. | Python |
items.forEach(function(c) {{ console.log(c); }}) | items.forEach((c) => {{ console.log(c); }}) | Arrow functions are cleaner. | JavaScript |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
#header {{ color: #fff; }} | #header {{ color: #fff; }} | Correct. | CSS |
if x = 2: | if x == 2: | Use == for comparison. | Python |
'hello' + 50 | 'hello' + str(50) | Can't add int to string. | Python |
SELECT * FROM users WHRE status=22; | SELECT * FROM users WHERE status=22; | Fix WHERE. | SQL |
if result = 35 | if result == 35 | Use ==. | Go |
print 'world' | print('world') | print needs parentheses. | Python |
let z: i32 = "test"; | let z: &str = "test"; | Type mismatch. | Rust |
print 'message' | print 'message'; | Add semicolon. | Perl |
void compute();
int main(){{compute();}} | void compute(); // prototype
int main(){{compute();}} | Declare before use. | C++ |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
{{"status":"hello",}} | {{"status":"hello"}} | Remove trailing comma. | JSON |
Order.save(); | Order.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
x <- 5; if (x > 3) print('large') | x <- 5; if (x > 3) print('large') | Correct. | R |
echo 'test' | echo 'test'; | Add semicolon. | PHP |
["world", 66] | ["world", 66] | Correct. | JSON |
34c = 10 | c34 = 10 | Variable cannot start with digit. | Python |
<person age=15> | <person age="15"> | Quote attribute. | XML |
if temp = 17 | if temp == 17 | Use ==. | MATLAB |
println('data') | println("data") | Double quotes. | Scala |
<div color=green> | <div style='color:green;'> | Use style attribute. | CSS |
<input type='text' value='hello'> | <input type='text' value='hello' name='id'> | Add name attribute. | HTML |
[34, 21, 75 | [34, 21, 75] | Close bracket. | Ruby |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.