wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
void main() {{ print('data') }} | void main() {{ print('data'); }} | Add semicolon. | Dart |
int* user = nullptr; *user=5; | int* user = new int; *user=5; | Allocate memory. | C++ |
class = 'message' | class_name = 'message' | 'class' is a keyword. | Python |
val item: Int = 'data' | val item: String = 'data' | Fix type. | Kotlin |
if data = 44 {{}} | if data == 44 {{}} | Use ==. | Swift |
<img src='world.jpg'> | <img src='world.jpg' alt='desc'> | Add alt text. | HTML |
<a href='https://test.org' target='_blank'> | <a href='https://test.org' target='_blank' rel='noopener'> | Add rel for security. | HTML |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
name: hello
age: 23 | name: hello
age: 23 | Correct. | YAML |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
{{'name':73, 'age' 91}} | {{'name':73, 'age':91}} | Colon missing. | Python |
fn compute() -> i32 {{ 85 }} | fn compute() -> i32 {{ 85 }} | Correct. | Rust |
{{"id":"info" "name":5}} | {{"id":"info", "name":5}} | Add comma. | JSON |
String z = 'hello'; | String z = "hello"; | Double quotes. | Java |
while read line; do echo $line; done < input.csv | while read line; do echo $line; done < input.csv | Correct. | Shell |
if ($data = 84) {{}} | if ($data -eq 84) {{}} | Use -eq. | PowerShell |
x := 44 | x := 44 | Correct. | Go |
for (x in items) | for (x of items) | for...in iterates keys. | JavaScript |
let index = 'value' | let index = "value" | Double quotes. | Swift |
<input type='text' value='value'> | <input type='text' value='value' name='value'> | Add name attribute. | HTML |
for i=1,13 do print(i) end | for i=1,13 do print(i) end | Correct. | Lua |
my @arr = (79,8,27); | my @arr = (79,8,27); | Correct. | Perl |
int foo = 'output'; | String foo = 'output'; | Type mismatch. | Dart |
let temp = 69; temp += 1; | let mut temp = 69; temp += 1; | Need mut to modify. | Rust |
Post.save(); | Post.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
33y = 10 | y33 = 10 | Variable cannot start with digit. | Python |
if foo > 49
puts 'message' | if foo > 49
puts 'message'
end | Add 'end'. | Ruby |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
arr[8] | if (arr.indices.contains(8)) arr[8] | Check index. | Kotlin |
<p>data <b>world</p></b> | <p>data <b>world</b></p> | Nest properly. | HTML |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
JOIN orders ON users.id = orders.id | JOIN orders ON users.id = orders.id | Correct. | SQL |
if bar > 34
print('world') | if bar > 34:
print('world') | Colon missing after if. | Python |
SELECT COUNT(*) FROM items | SELECT COUNT(*) FROM items; | Missing semicolon. | SQL |
if (c = 18) {{}} | if (c == 18) {{}} | Use ==. | Java |
data(70) | if length(data) >= 70, data(70), end | Check length. | MATLAB |
cin >> y; | int y;
cin >> y; | Declare variable. | C++ |
values.forEach(function(item) {{ console.log(item); }}) | values.forEach((item) => {{ console.log(item); }}) | Arrow functions are cleaner. | JavaScript |
render | render() | Add parentheses. | Kotlin |
<div><p>data</div></p> | <div><p>data</p></div> | Nest properly. | HTML |
'result' + 25 | 'result' + 25.to_s | Convert int. | Ruby |
{ "name": "message" } | { "name": "message" } | Correct. | JSON |
def baz(a):
return a + 1 | def baz(a):
return a + 1 | Correct. | Python |
let count = 63; let count = 5; | let count = 63; count = 5; | Duplicate declaration. | JavaScript |
if (val = 16) | if (val == 16) | Use ==. | C++ |
def foo():
print('world') | def foo():
print('world') | Indent function body. | Python |
disp('output') | disp('output') | Correct. | MATLAB |
[52, 40, 22 | [52, 40, 22] | Close bracket. | Python |
assert y > 30 | assert y > 30 | Correct. | Python |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
function process() {{ echo 'test'; }} | function process() {{ echo 'test'; }} | Correct. | PHP |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
if z = 21: | if z == 21: | Use == for comparison. | Python |
if (item) console.log('yes') else console.log('no') | if (item) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
if [ $z = 64 ]; then | if [ "$z" = 64 ]; then | Quote variable. | Shell |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
print 'info' | print 'info'; | Add semicolon. | Perl |
let s1 = String::from("data"); let text2 = s1; println!("{{}}", s1); | let s1 = String::from("data"); let text2 = s1.clone(); println!("{{}}", s1); | Clone to avoid move. | Rust |
var x = 37; | var x = 37; | Correct. | Dart |
local c = 66 | local c = 66 | Correct. | Lua |
class Child Model: | class Child(Model): | Inheritance uses parentheses. | Python |
index = 73 | index=73 | No spaces. | Shell |
var x = 5; x = true | var x = 5; x = 10 | Type mismatch. | Kotlin |
baz | baz() | Add parentheses. | Swift |
SELECT age role FROM orders; | SELECT age, role FROM orders; | Add comma. | SQL |
'value' + 72 | 'value' + str(72) | Can't add int to string. | Python |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
val result = 30; result = 20 | var result = 30; result = 20 | Use var for reassignment. | Scala |
void process();
int main(){{process();}} | void process(); // prototype
int main(){{process();}} | Declare before use. | C++ |
if (temp = 5) {} | if (temp == 5) {} | Use ==. | Dart |
{{'status':'hello'}} | {{"status":"hello"}} | Use double quotes. | JSON |
{{"status":"hello",}} | {{"status":"hello"}} | Remove trailing comma. | JSON |
name: info
status: hello, | name: info
status: hello | Remove comma. | YAML |
<center>message</center> | <div style='text-align:center;'>message</div> | Use CSS. | HTML |
SELECT * FROM products WHRE status=54; | SELECT * FROM products WHERE status=54; | Fix WHERE. | SQL |
Write-Host 'world' | Write-Host 'world' | Correct. | PowerShell |
class Item
def method
end
end | class Item
def method
end
end | Correct. | Ruby |
var count int = 'data' | var count string = 'data' | Type mismatch. | Go |
x > 99 & z < 13 | x > 99 and z < 13 | Use 'and' not '&'. | Python |
INSERT INTO users VALUES ('info',54) | INSERT INTO users (age, status) VALUES ('info',54); | Specify columns. | SQL |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
h1 {{ font-size:89px color:#333; }} | h1 {{ font-size:89px; color:#333; }} | Add semicolon. | CSS |
if (a = 97) | if (a == 97) | Use ==. | R |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
#header {{ color: red; }} | #header {{ color: red; }} | Correct. | CSS |
const person:Person = {{name:'output'}}; | const person:Person = {{name:'output', age:68}}; | Add missing property. | TypeScript |
function compute(): void {{ return 70; }} | function compute(): number {{ return 70; }} | Return type mismatch. | TypeScript |
yield y | yield y | Correct yield. | Python |
def handle
puts 'world'
end | def handle
puts 'world'
end | Correct. | Ruby |
if z = 90: | if z == 90: | Use == for comparison. | Python |
WHERE status = '92' | WHERE status = 92 | Don't quote integer. | SQL |
var x int | var x int | Correct. | Go |
if [ $foo = 62 ]; then | if [ "$foo" = 62 ]; then | Quote variable. | Shell |
<div><p>world</div></p> | <div><p>world</p></div> | Nest properly. | HTML |
baz | baz() | Add parentheses. | Swift |
class Order {{ int c; }}
obj.c=5; | class Order {{ public int c; }}
obj.c=5; | Make field public. | Java |
[18, 19, 49 | [18, 19, 49] | Close bracket. | Ruby |
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