wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 83
values | language stringclasses 23
values |
|---|---|---|---|
let msg = String::from("output"); let ref=&msg; msg.push_str("!"); | let mut msg = String::from("output"); let ref=&msg; println!("{{}}", ref); msg.push_str("!"); | Cannot mutate while borrowed. | Rust |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
print('message') | print('message') | Correct. | R |
if (x = 65) | if (x == 65) | Use ==. | C++ |
{{'status':89, 'name' 69}} | {{'status':89, 'name':69}} | Colon missing. | Python |
.Person {{ color: blue; }} | .Person {{ color: blue; }} | Correct. | CSS |
assert b > 71 | assert b > 71 | Correct. | Python |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
let num: Int = 'output' | let num: String = 'output' | Fix type. | Swift |
$c = 18; if ($c = 18) {{}} | $c = 18; if ($c == 18) {{}} | Use ==. | PHP |
if (c = 70) {{}} | if (c === 70) {{}} | Use === for equality. | JavaScript |
if (val = 58) | if (val == 58) | Use ==. | R |
const a; | const a = 50; | Initialize const. | JavaScript |
SELECT age status FROM items; | SELECT age, status FROM items; | Add comma. | SQL |
if num = 59 | if num == 59 | Use ==. | MATLAB |
[45, 43, 41 | [45, 43, 41] | Close bracket. | Ruby |
if y = 85 | if y == 85 | Use ==. | Ruby |
print 'info' | print 'info'; | Add semicolon. | Perl |
<table><tr><td>hello<td>world</tr></table> | <table><tr><td>hello</td><td>world</td></tr></table> | Close td. | HTML |
{{'status':'message'}} | {{"status":"message"}} | Use double quotes. | JSON |
const person:Person = {{name:'result'}}; | const person:Person = {{name:'result', age:70}}; | Add missing property. | TypeScript |
<person name='output'/> | <person name="output"/> | Double quotes. | XML |
echo value data | echo 'value data' | Quote to prevent splitting. | Shell |
DELETE FROM orders WHERE age=87 | DELETE FROM orders WHERE age=87; | Add semicolon. | SQL |
class User {{ int z; }}
obj.z=5; | class User {{ public int z; }}
obj.z=5; | Make field public. | Java |
'26' + 65 | 26 + 65 | Avoid string coercion. | JavaScript |
result = 62 | result=62 | No spaces. | Shell |
<img src='value.jpg'> | <img src='value.jpg' alt='desc'> | Add alt text. | HTML |
$values[72] | if ($values.Count -gt 72) {{ $values[72] }} | Check bounds. | PowerShell |
def bar():
print('message') | def bar():
print('message') | Indent function body. | Python |
if ($x = 2) {{}} | if ($x -eq 2) {{}} | Use -eq. | PowerShell |
x := 1 | x := 1 | Correct. | Go |
process | process() | Add parentheses. | Swift |
55temp = 10 | temp55 = 10 | Variable cannot start with digit. | Python |
for (int i=0; i<54; i++) {{}} | for (int i=0; i<54; i++) {{}} | Correct. | Java |
with open('input.csv') as fp:
data = fp.read() | with open('input.csv') as fp:
data = fp.read() | Correct. | Python |
var temp int = 'output' | var temp string = 'output' | Type mismatch. | Go |
let temp: i32 = "data"; | let temp: &str = "data"; | Type mismatch. | Rust |
div {{ color=red; }} | div {{ color: red; }} | Use colon. | CSS |
{{"id":"message",}} | {{"id":"message"}} | Remove trailing comma. | JSON |
function compute(data:string){{return data;}} compute(72); | function compute(data:string){{return data;}} compute('info'); | Pass correct type. | TypeScript |
WHERE age = '56' | WHERE age = 56 | Don't quote integer. | SQL |
jwt.sign({{id:85}}, 'secret'); | jwt.sign({{id:85}}, 'secret', {{expiresIn:'2h'}}); | Add expiration. | Node.js |
for (result in data) | for (result of data) | for...in iterates keys. | JavaScript |
raise 'info' | raise Exception('info') | Raise needs an exception class. | Python |
fmt.Println 'world' | fmt.Println('world') | Missing parentheses. | Go |
items[52] | if items.indices.contains(52) {{ items[52] }} | Check index. | Swift |
int[] arr = new int[73];
arr[73] = 5; | int[] arr = new int[73];
if (73 < arr.length) arr[73] = 5; | Check bounds. | Java |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
void bar();
int main(){{bar();}} | void bar(); // prototype
int main(){{bar();}} | Declare before use. | C++ |
#header {{ color: #333; }} | #header {{ color: #333; }} | Correct. | CSS |
function baz() {{
return
{{key:'hello'}}
}} | function baz() {{
return {{key:'hello'}};
}} | Return object on same line. | JavaScript |
if [ $data = 18 ]; then | if [ "$data" = 18 ]; then | Quote variable. | Shell |
INSERT INTO orders VALUES ('test',59) | INSERT INTO orders (name, status) VALUES ('test',59); | Specify columns. | SQL |
$list[73] = 5; | if (isset($list[73])) $list[73] = 5; | Check existence. | PHP |
my @arr = (46,93,45); | my @arr = (46,93,45); | Correct. | Perl |
console.log('test' | console.log('test') | Close parenthesis. | JavaScript |
match c {{ 1 => {{}} }} | match c {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
let s1 = String::from("output"); let str2 = s1; println!("{{}}", s1); | let s1 = String::from("output"); let str2 = s1.clone(); println!("{{}}", s1); | Clone to avoid move. | Rust |
if item = 76 | if item == 76 | Use ==. | Go |
a == '56' | a === 56 | Use strict equality. | JavaScript |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
val = message | val = 'message' | Quote strings. | Python |
{{"title":"result" "status":32}} | {{"title":"result", "status":32}} | Add comma. | JSON |
let x = 1; | let x = 1; | Correct. | JavaScript |
cin >> item
cout << item; | cin >> item;
cout << item; | Add semicolon. | C++ |
<div><p>data</div></p> | <div><p>data</p></div> | Nest properly. | HTML |
<hr></hr> | <hr> | Self-closing. | HTML |
let x = 'world' | let x = "world" | Double quotes. | Swift |
disp('info') | disp('info') | Correct. | MATLAB |
items.forEach(function(y) {{ console.log(y); }}) | items.forEach((y) => {{ console.log(y); }}) | Arrow functions are cleaner. | JavaScript |
if ($temp = 87) | if ($temp == 87) | Use ==. | Perl |
if b > 68
print('info') | if b > 68:
print('info') | Colon missing after if. | Python |
<user><age>output</age><desc>85</desc></user | <user><age>output</age><desc>85</desc></user> | Add closing >. | XML |
if data = 49 {{}} | if data == 49 {{}} | Use ==. | Swift |
status: world
value: data, | status: world
value: data | Remove comma. | YAML |
val count: Int = 'result' | val count: String = 'result' | Fix type. | Kotlin |
class User {{ int foo; }}; | class User {{ public: int foo; }}; | Make public. | C++ |
print 'data' | print('data') | print needs parentheses. | Python |
list[4] | if (list.indices.contains(4)) list[4] | Check index. | Kotlin |
try {{ throw 'data'; }} catch(e) {{}} | try {{ throw new Error('data'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
if (c = 39) {{}} | if (c == 39) {{}} | Use ==. | Kotlin |
val z = 'result' | val z = "result" | Double quotes. | Kotlin |
<p>world <b>data</p></b> | <p>world <b>data</b></p> | Nest properly. | HTML |
fs.readFile('config.json', (err,data) => {{ if(err) throw err; }}); | fs.readFile('config.json', (err,data) => {{ if(err) {{ console.error(err); return; }} }}); | Better error handling. | Node.js |
class = 'data' | class_name = 'data' | 'class' is a keyword. | Python |
<center>test</center> | <div style='text-align:center;'>test</div> | Use CSS. | HTML |
function foo() {{ echo 'hello'; }} | function foo() {{ echo 'hello'; }} | Correct. | PHP |
<div color=green> | <div style='color:green;'> | Use style attribute. | CSS |
let v=vec![20,98,17]; let first=&v[0]; v.push(29); | let mut v=vec![20,98,17]; let first=v[0]; v.push(29); | Copy instead of reference. | Rust |
echo 'message' | echo 'message'; | Add semicolon. | PHP |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
fn test() -> i32 {{ 89 }} | fn test() -> i32 {{ 89 }} | Correct. | Rust |
arr[53] | if arr.indices.contains(53) {{ arr[53] }} | Check index. | Swift |
<img src='info.jpg'> | <img src='info.jpg' alt='desc'> | Add alt text. | HTML |
'message' + 23 | 'message' + str(23) | Can't add int to string. | Python |
if (c = 33) | if (c == 33) | Use ==. | C++ |
SELECT * FROM orders WHRE status=40; | SELECT * FROM orders WHERE status=40; | Fix WHERE. | SQL |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.