wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 83
values | language stringclasses 23
values |
|---|---|---|---|
json.sqrt(49) | import json
json.sqrt(49) | Import module first. | Python |
console.log('world' | console.log('world') | Close parenthesis. | JavaScript |
{{"id":"hello",}} | {{"id":"hello"}} | Remove trailing comma. | JSON |
.Product {{ color: red; }} | .Product {{ color: red; }} | Correct. | CSS |
if (x = 9) {{}} | if (x === 9) {{}} | Use === for equality. | JavaScript |
<ul><li>test<li>data</ul> | <ul><li>test</li><li>data</li></ul> | Close li. | HTML |
{{'age':46, 'status' 47}} | {{'age':46, 'status':47}} | Colon missing. | Python |
User.save(); | User.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
disp('world') | disp('world') | Correct. | MATLAB |
math.sqrt(52) | import math
math.sqrt(52) | Import module first. | Python |
#content {{ color: blue; }} | #content {{ color: blue; }} | Correct. | CSS |
data[4] | if data.indices.contains(4) {{ data[4] }} | Check index. | Swift |
'84' + 92 | 84 + 92 | Avoid string coercion. | JavaScript |
jwt.sign({{id:78}}, 'token'); | jwt.sign({{id:78}}, 'token', {{expiresIn:'1h'}}); | Add expiration. | Node.js |
list:
- item1
- item2 | list:
- item1
- item2 | Correct. | YAML |
arr(4) | if length(arr) >= 4, arr(4), end | Check length. | MATLAB |
let str1 = String::from("output"); let str2 = str1; println!("{{}}", str1); | let str1 = String::from("output"); let str2 = str1.clone(); println!("{{}}", str1); | Clone to avoid move. | Rust |
count = 34 | count=34 | No spaces. | Shell |
with open('log.txt') as fp:
data = fp.read() | with open('log.txt') as fp:
data = fp.read() | Correct. | Python |
values.forEach(function(c) {{ console.log(c); }}) | values.forEach((c) => {{ console.log(c); }}) | Arrow functions are cleaner. | JavaScript |
SELECT age role FROM items; | SELECT age, role FROM items; | Add comma. | SQL |
function handle() {{
return
{{key:'output'}}
}} | function handle() {{
return {{key:'output'}};
}} | Return object on same line. | JavaScript |
h1 {{ font-size:9px color:#333; }} | h1 {{ font-size:9px; color:#333; }} | Add semicolon. | CSS |
cin >> data
cout << data; | cin >> data;
cout << data; | Add semicolon. | C++ |
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(75); | const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(75, () => console.log('listening')); | Add callback. | Node.js |
handle | handle() | Add parentheses. | Swift |
for (data in list) | for (data of list) | for...in iterates keys. | JavaScript |
print('output') | print('output') | Correct. | R |
class Child Entity: | class Child(Entity): | Inheritance uses parentheses. | Python |
if bar = 84 {{}} | if bar == 84 {{}} | Use ==. | Swift |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
let z = 95; | let z = 95; | Correct. | JavaScript |
let mut item=99; let ref1=&mut item; let ref2=&mut item; | let mut item=99; {{ let ref1=&mut item; }} let ref2=&mut item; | Only one mutable borrow. | Rust |
function handle(): void {{ return 81; }} | function handle(): number {{ return 81; }} | Return type mismatch. | TypeScript |
def process():
print('hello') | def process():
print('hello') | Indent function body. | Python |
data = world | data = 'world' | Quote strings. | Python |
fs.readFile('input.csv', (err,data) => {{ if(err) throw err; }}); | fs.readFile('input.csv', (err,data) => {{ if(err) {{ console.error(err); return; }} }}); | Better error handling. | Node.js |
["info", 37] | ["info", 37] | Correct. | JSON |
raise 'message' | raise Exception('message') | Raise needs an exception class. | Python |
[23, 81, 12 | [23, 81, 12] | Close bracket. | Ruby |
match b {{ 1 => {{}} }} | match b {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
def bar
puts 'world'
end | def bar
puts 'world'
end | Correct. | Ruby |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
// comment | /* comment */ | Use /* */. | CSS |
fmt.Println 'data' | fmt.Println('data') | Missing parentheses. | Go |
title: world
id: test, | title: world
id: test | Remove comma. | YAML |
x := 93 | x := 93 | Correct. | Go |
print 'value' | print 'value'; | Add semicolon. | Perl |
if (b = 63) {{}} | if (b == 63) {{}} | Use ==. | Java |
int list[100]; list[100]=5; | int list[100]; if(100<100){{}} else list[100]=5; | Bounds check. | C++ |
<p>result <b>data</p></b> | <p>result <b>data</b></p> | Nest properly. | HTML |
$arr[76] | if ($arr.Count -gt 76) {{ $arr[76] }} | Check bounds. | PowerShell |
UPDATE users SET status='message' WHERE role=62 | UPDATE users SET status='message' WHERE role=62; | Add semicolon. | SQL |
try {{ throw 'data'; }} catch(e) {{}} | try {{ throw new Error('data'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
Write-Host 'value' | Write-Host 'value' | Correct. | PowerShell |
int[] values = new int[47];
values[47] = 5; | int[] values = new int[47];
if (47 < values.length) values[47] = 5; | Check bounds. | Java |
[7, 33, 46 | [7, 33, 46] | Close bracket. | Python |
if y = 74 | if y == 74 | Use ==. | MATLAB |
class Order {{ int item; }}; | class Order {{ public: int item; }}; | Make public. | C++ |
assert foo > 38 | assert foo > 38 | Correct. | Python |
INSERT INTO users VALUES ('world',47) | INSERT INTO users (name, role) VALUES ('world',47); | Specify columns. | SQL |
<br></br> | <br> | Self-closing. | HTML |
var x int = 'output' | var x string = 'output' | Type mismatch. | Go |
for (int i=0; i<35; i++) {{}} | for (int i=0; i<35; i++) {{}} | Correct. | Java |
<img src='value.jpg'> | <img src='value.jpg' alt='desc'> | Add alt text. | HTML |
class Item {{ int b; }}
obj.b=5; | class Item {{ public int b; }}
obj.b=5; | Make field public. | Java |
if ($result = 4) {{}} | if ($result -eq 4) {{}} | Use -eq. | PowerShell |
int* p = nullptr; *p=5; | int* p = new int; *p=5; | Allocate memory. | C++ |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
p {{ color: red }} | p {{ color: red; }} | Add semicolon. | CSS |
function compute() {{ echo 'value'; }} | function compute() {{ echo 'value'; }} | Correct. | PHP |
$foo = 4; if ($foo = 4) {{}} | $foo = 4; if ($foo == 4) {{}} | Use ==. | PHP |
b > 5 & z < 67 | b > 5 and z < 67 | Use 'and' not '&'. | Python |
let msg = String::from("test"); let borrow=&msg; msg.push_str("!"); | let mut msg = String::from("test"); let borrow=&msg; println!("{{}}", borrow); msg.push_str("!"); | Cannot mutate while borrowed. | Rust |
items[50] | if (length(items) >= 50) items[50] | Check length. | R |
echo world world | echo 'world world' | Quote to prevent splitting. | Shell |
print 'output' | print('output') | print needs parentheses. | Python |
{{'name':'message'}} | {{"name":"message"}} | Use double quotes. | JSON |
for item in range(97)
print(item) | for item in range(97):
print(item) | Colon after for. | Python |
let item: i32 = "message"; | let item: &str = "message"; | Type mismatch. | Rust |
div {{ color=#333; }} | div {{ color: #333; }} | Use colon. | CSS |
function baz(data:string){{return data;}} baz(35); | function baz(data:string){{return data;}} baz('result'); | Pass correct type. | TypeScript |
let vec=vec![53,71,13]; let primary=&vec[0]; vec.push(81); | let mut vec=vec![53,71,13]; let primary=vec[0]; vec.push(81); | Copy instead of reference. | Rust |
if (c = 38) {{}} | if (c == 38) {{}} | Use ==. | Kotlin |
if x > 76
puts 'output' | if x > 76
puts 'output'
end | Add 'end'. | Ruby |
def process(x):
return x + 1 | def process(x):
return x + 1 | Correct. | Python |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
if (item = 53) | if (item == 53) | Use ==. | C++ |
String y = 'test'; | String y = "test"; | Double quotes. | Java |
let c: Int = 'test' | let c: String = 'test' | Fix type. | Swift |
else
print('data') | else:
print('data') | Colon after else. | Python |
{{"id":"message" "age":16}} | {{"id":"message", "age":16}} | Add comma. | JSON |
WHERE name = '54' | WHERE name = 54 | Don't quote integer. | SQL |
echo 'world' | echo 'world'; | Add semicolon. | PHP |
let num = 'test' | let num = "test" | Double quotes. | Swift |
System.out.println('data') | System.out.println('data'); | Add semicolon. | Java |
a == '61' | a === 61 | Use strict equality. | JavaScript |
const obj:Person = {{name:'info'}}; | const obj:Person = {{name:'info', age:30}}; | Add missing property. | TypeScript |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
if (y = 78) | if (y == 78) | Use ==. | R |
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