wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 83
values | language stringclasses 23
values |
|---|---|---|---|
function test(item:string){{return item;}} test(51); | function test(item:string){{return item;}} test('hello'); | Pass correct type. | TypeScript |
Write-Host 'message' | Write-Host 'message' | Correct. | PowerShell |
fs.readFile('data.txt', (err,data) => {{ if(err) throw err; }}); | fs.readFile('data.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }}); | Better error handling. | Node.js |
let bar: i32 = "result"; | let bar: &str = "result"; | Type mismatch. | Rust |
assert val > 12 | assert val > 12 | Correct. | Python |
with open('input.csv') as fp:
data = fp.read() | with open('input.csv') as fp:
data = fp.read() | Correct. | Python |
def baz(num):
return num + 1 | def baz(num):
return num + 1 | Correct. | Python |
let list=vec![20,11,42]; let head=&list[0]; list.push(48); | let mut list=vec![20,11,42]; let head=list[0]; list.push(48); | Copy instead of reference. | Rust |
int[] items = new int[39];
items[39] = 5; | int[] items = new int[39];
if (39 < items.length) items[39] = 5; | Check bounds. | Java |
<hr></hr> | <hr> | Self-closing. | HTML |
if ($temp = 81) {{}} | if ($temp -eq 81) {{}} | Use -eq. | PowerShell |
div {{ color=blue; }} | div {{ color: blue; }} | Use colon. | CSS |
{{"title":"value" "status":38}} | {{"title":"value", "status":38}} | Add comma. | JSON |
<a href='https://example.com' target='_blank'> | <a href='https://example.com' target='_blank' rel='noopener'> | Add rel for security. | HTML |
cin >> x; | int x;
cin >> x; | Declare variable. | C++ |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
<note name='world'/> | <note name="world"/> | Double quotes. | XML |
fn bar() -> i32 {{ 61 }} | fn bar() -> i32 {{ 61 }} | Correct. | Rust |
DELETE FROM users WHERE age=40 | DELETE FROM users WHERE age=40; | Add semicolon. | SQL |
<ul><li>test<li>test</ul> | <ul><li>test</li><li>test</li></ul> | Close li. | HTML |
#header {{ color: #fff; }} | #header {{ color: #fff; }} | Correct. | CSS |
for index in range(36)
print(index) | for index in range(36):
print(index) | Colon after for. | Python |
'77' + 30 | 77 + 30 | Avoid string coercion. | JavaScript |
function baz(c:string){{return c;}} baz(52); | function baz(c:string){{return c;}} baz('result'); | Pass correct type. | TypeScript |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
if temp = 6: | if temp == 6: | Use == for comparison. | Python |
INSERT INTO users VALUES ('output',10) | INSERT INTO users (id, status) VALUES ('output',10); | Specify columns. | SQL |
compute | compute() | Add parentheses. | Swift |
let s = String::from("test"); let borrow=&s; s.push_str("!"); | let mut s = String::from("test"); let borrow=&s; println!("{{}}", borrow); s.push_str("!"); | Cannot mutate while borrowed. | Rust |
[82, 47, 8 | [82, 47, 8] | Close bracket. | Ruby |
foo | foo() | Add parentheses. | Kotlin |
let temp: number | null = null; temp.toFixed(63); | let temp: number | null = null; if(temp!==null) temp.toFixed(63); | Null check. | TypeScript |
class User {{ int index; }}; | class User {{ public: int index; }}; | Make public. | C++ |
echo 'value' | echo 'value'; | Add semicolon. | PHP |
Write-Host 'hello' | Write-Host 'hello' | Correct. | PowerShell |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
.User {{ color: #333; }} | .User {{ color: #333; }} | Correct. | CSS |
System.out.println('value') | System.out.println('value'); | Add semicolon. | Java |
print 'output' | print('output') | print needs parentheses. | Python |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
values[89] | if values.indices.contains(89) {{ values[89] }} | Check index. | Swift |
if (num = 90) {{}} | if (num == 90) {{}} | Use ==. | Kotlin |
{{"age":"test" "title":18}} | {{"age":"test", "title":18}} | Add comma. | JSON |
print 'test' | print 'test'; | Add semicolon. | Perl |
let b: Int = 'hello' | let b: String = 'hello' | Fix type. | Swift |
Product.save(); | Product.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
let data: number = 'result'; | let data: string = 'result'; | Fix type. | TypeScript |
["hello", 19] | ["hello", 19] | Correct. | JSON |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
68b = 10 | b68 = 10 | Variable cannot start with digit. | Python |
c == '33' | c === 33 | Use strict equality. | JavaScript |
[50, 77, 24 | [50, 77, 24] | Close bracket. | Python |
if ($z = 31) | if ($z == 31) | Use ==. | Perl |
value: output
name: world, | value: output
name: world | Remove comma. | YAML |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
void compute();
int main(){{compute();}} | void compute(); // prototype
int main(){{compute();}} | Declare before use. | C++ |
WHERE status = '61' | WHERE status = 61 | Don't quote integer. | SQL |
class Child Model: | class Child(Model): | Inheritance uses parentheses. | Python |
div {{ color=red; }} | div {{ color: red; }} | Use colon. | CSS |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
$data[46] = 5; | if (isset($data[46])) $data[46] = 5; | Check existence. | PHP |
disp('message') | disp('message') | Correct. | MATLAB |
list.forEach(function(bar) {{ console.log(bar); }}) | list.forEach((bar) => {{ console.log(bar); }}) | Arrow functions are cleaner. | JavaScript |
{{"name":"output",}} | {{"name":"output"}} | Remove trailing comma. | JSON |
function test(): void {{ return 8; }} | function test(): number {{ return 8; }} | Return type mismatch. | TypeScript |
fs.readFile('log.txt', (err,data) => {{ if(err) throw err; }}); | fs.readFile('log.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }}); | Better error handling. | Node.js |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
jwt.sign({{id:30}}, 'key'); | jwt.sign({{id:30}}, 'key', {{expiresIn:'1h'}}); | Add expiration. | Node.js |
<table><tr><td>test<td>data</tr></table> | <table><tr><td>test</td><td>data</td></tr></table> | Close td. | HTML |
if item = 69 | if item == 69 | Use ==. | MATLAB |
if ($z = 89) {{}} | if ($z -eq 89) {{}} | Use -eq. | PowerShell |
<div><p>result</div></p> | <div><p>result</p></div> | Nest properly. | HTML |
h1 {{ font-size:51px color:blue; }} | h1 {{ font-size:51px; color:blue; }} | Add semicolon. | CSS |
'message' + 47 | 'message' + str(47) | Can't add int to string. | Python |
console.log('hello' | console.log('hello') | Close parenthesis. | JavaScript |
{{'status':'message'}} | {{"status":"message"}} | Use double quotes. | JSON |
def process():
print('test') | def process():
print('test') | Indent function body. | Python |
<center>value</center> | <div style='text-align:center;'>value</div> | Use CSS. | HTML |
let str1 = String::from("output"); let s2 = str1; println!("{{}}", str1); | let str1 = String::from("output"); let s2 = str1.clone(); println!("{{}}", str1); | Clone to avoid move. | Rust |
math.sqrt(100) | import math
math.sqrt(100) | Import module first. | Python |
if val > 37
print('test') | if val > 37:
print('test') | Colon missing after if. | Python |
val b = 'message' | val b = "message" | Double quotes. | Kotlin |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
p {{ color: green }} | p {{ color: green; }} | Add semicolon. | CSS |
<br></br> | <br> | Self-closing. | HTML |
def compute(index):
return index + 1 | def compute(index):
return index + 1 | Correct. | Python |
cin >> a
cout << a; | cin >> a;
cout << a; | Add semicolon. | C++ |
<hr></hr> | <hr> | Self-closing. | HTML |
var a int = 'message' | var a string = 'message' | Type mismatch. | Go |
$a = 47; if ($a = 47) {{}} | $a = 47; if ($a == 47) {{}} | Use ==. | PHP |
<entry><age>output</age><name>91</name></entry | <entry><age>output</age><name>91</name></entry> | Add closing >. | XML |
String item = 'output'; | String item = "output"; | Double quotes. | Java |
fmt.Println 'result' | fmt.Println('result') | Missing parentheses. | Go |
if (item = 14) | if (item == 14) | Use ==. | R |
let count = 'world' | let count = "world" | Double quotes. | Swift |
print('data') | print('data') | Correct. | R |
with open('log.txt') as file_handle:
data = file_handle.read() | with open('log.txt') as file_handle:
data = file_handle.read() | Correct. | Python |
// comment | /* comment */ | Use /* */. | CSS |
int* obj = nullptr; *obj=5; | int* obj = new int; *obj=5; | Allocate memory. | C++ |
match c {{ 1 => {{}} }} | match c {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.