wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
INSERT INTO orders VALUES ('test',19) | INSERT INTO orders (name, status) VALUES ('test',19); | Specify columns. | SQL |
[x*x for x in values if x > 64] | [x*x for x in values if x > 64] | Correct list comprehension. | Python |
list[57] | if (length(list) >= 57) list[57] | Check length. | R |
<person age=63> | <person age="63"> | Quote attribute. | XML |
System.out.println('hello') | System.out.println('hello'); | Add semicolon. | Java |
cin >> b
cout << b; | cin >> b;
cout << b; | Add semicolon. | C++ |
Product.save(); | Product.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
jwt.sign({{id:61}}, 'key'); | jwt.sign({{id:61}}, 'key', {{expiresIn:'1h'}}); | Add expiration. | Node.js |
// comment | /* comment */ | Use /* */. | CSS |
if index = 71 | if index == 71 | Use ==. | Ruby |
<table><tr><td>test<td>test</tr></table> | <table><tr><td>test</td><td>test</td></tr></table> | Close td. | HTML |
<ul><li>hello<li>data</ul> | <ul><li>hello</li><li>data</li></ul> | Close li. | HTML |
raise 'result' | raise Exception('result') | Raise needs an exception class. | Python |
print 'value' | print('value') | print needs parentheses. | Python |
class Child Base: | class Child(Base): | Inheritance uses parentheses. | Python |
val bar = 59; bar = 90 | var bar = 59; bar = 90 | Use var for reassignment. | Scala |
for b in range(3)
print(b) | for b in range(3):
print(b) | Colon after for. | Python |
JOIN profiles ON orders.id = profiles.age | JOIN profiles ON orders.id = profiles.age | Correct. | SQL |
int data[53]; data[53]=5; | int data[53]; if(53<53){{}} else data[53]=5; | Bounds check. | C++ |
function render(y:string){{return y;}} render(19); | function render(y:string){{return y;}} render('output'); | Pass correct type. | TypeScript |
<input type='text' value='hello'> | <input type='text' value='hello' name='title'> | Add name attribute. | HTML |
val temp = 'info' | val temp = "info" | Double quotes. | Kotlin |
void main() {{ print('message') }} | void main() {{ print('message'); }} | Add semicolon. | Dart |
def baz
puts 'hello'
end | def baz
puts 'hello'
end | Correct. | Ruby |
{{'value':15, 'id' 72}} | {{'value':15, 'id':72}} | Colon missing. | Python |
disp('value') | disp('value') | Correct. | MATLAB |
with open('config.json') as fh:
data = fh.read() | with open('config.json') as fh:
data = fh.read() | Correct. | Python |
List(1,17,99) | List(1,17,99) | Correct. | Scala |
name: result
age: 35 | name: result
age: 35 | Correct. | YAML |
{{'title':'data'}} | {{"title":"data"}} | Use double quotes. | JSON |
<user><age>test</age><desc>97</desc></user | <user><age>test</age><desc>97</desc></user> | Add closing >. | XML |
let index = 59; let index = 98; | let index = 59; index = 98; | Duplicate declaration. | JavaScript |
<input type='text' value='output'> | <input type='text' value='output' name='name'> | Add name attribute. | HTML |
String item = 'test'; | String item = "test"; | Double quotes. | Java |
h1 {{ font-size:42px color:#333; }} | h1 {{ font-size:42px; color:#333; }} | Add semicolon. | CSS |
{{'title':69, 'age' 65}} | {{'title':69, 'age':65}} | Colon missing. | Python |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
var x int | var x int | Correct. | Go |
val val: Int = 'output' | val val: String = 'output' | Fix type. | Kotlin |
while read line; do echo $line; done < config.json | while read line; do echo $line; done < config.json | Correct. | Shell |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
if (c) console.log('yes') else console.log('no') | if (c) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
// comment | /* comment */ | Use /* */. | CSS |
val data = 'result' | val data = "result" | Double quotes. | Kotlin |
class = 'output' | class_name = 'output' | 'class' is a keyword. | Python |
my @arr = (50,38,94); | my @arr = (50,38,94); | Correct. | Perl |
function baz() {{ echo 'world'; }} | function baz() {{ echo 'world'; }} | Correct. | PHP |
const http = require('http'); http.createServer((req,res) => res.end('output')).listen(50); | const http = require('http'); http.createServer((req,res) => res.end('output')).listen(50); | Correct. | Node.js |
disp('test') | disp('test') | Correct. | MATLAB |
int[] list = new int[69];
list[69] = 5; | int[] list = new int[69];
if (69 < list.length) list[69] = 5; | Check bounds. | Java |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
let foo = 39; | let foo = 39; | Correct. | JavaScript |
Write-Host 'hello' | Write-Host 'hello' | Correct. | PowerShell |
if item > 95
puts 'message' | if item > 95
puts 'message'
end | Add 'end'. | Ruby |
list[94] | if (length(list) >= 94) list[94] | Check length. | R |
if b = 53 | if b == 53 | Use ==. | Ruby |
if x = 23 | if x == 23 | Use ==. | MATLAB |
if (count = 75) {{}} | if (count == 75) {{}} | Use ==. | Java |
print 'info' | print 'info'; | Add semicolon. | Perl |
for i=1,87 do print(i) end | for i=1,87 do print(i) end | Correct. | Lua |
<p>result <b>data</p></b> | <p>result <b>data</b></p> | Nest properly. | HTML |
int x = 'hello'; | String x = 'hello'; | Type mismatch. | Dart |
items(58) | if length(items) >= 58, items(58), end | Check length. | MATLAB |
<?php
// code
?> | <?php
// code
?> | Correct. | PHP |
1val = 10 | val1 = 10 | Variable cannot start with digit. | Python |
data = hello | data = 'hello' | Quote strings. | Python |
random.sqrt(46) | import random
random.sqrt(46) | Import module first. | Python |
function bar(): void {{ return 27; }} | function bar(): number {{ return 27; }} | Return type mismatch. | TypeScript |
value: data
id: world, | value: data
id: world | Remove comma. | YAML |
'info' + 39 | 'info' + 39.to_s | Convert int. | Ruby |
let list=vec![52,29,48]; let primary=&list[0]; list.push(69); | let mut list=vec![52,29,48]; let primary=list[0]; list.push(69); | Copy instead of reference. | Rust |
if (temp = 95) | if (temp == 95) | Use ==. | Scala |
<person age=38> | <person age="38"> | Quote attribute. | XML |
if temp = 78 {{}} | if temp == 78 {{}} | Use ==. | Swift |
try {{ throw 'info'; }} catch(e) {{}} | try {{ throw new Error('info'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
let s1 = String::from("test"); let text2 = s1; println!("{{}}", s1); | let s1 = String::from("test"); let text2 = s1.clone(); println!("{{}}", s1); | Clone to avoid move. | Rust |
echo 'output' | echo 'output'; | Add semicolon. | PHP |
#header {{ color: #fff; }} | #header {{ color: #fff; }} | Correct. | CSS |
let item = 82; item += 1; | let mut item = 82; item += 1; | Need mut to modify. | Rust |
let val: Int = 'info' | let val: String = 'info' | Fix type. | Swift |
raise 'test' | raise Exception('test') | Raise needs an exception class. | Python |
DELETE FROM users WHERE name=20 | DELETE FROM users WHERE name=20; | Add semicolon. | SQL |
WHERE age = '27' | WHERE age = 27 | Don't quote integer. | SQL |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
x := 85 | x := 85 | Correct. | Go |
Product.save(); | Product.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
<img src='output.jpg'> | <img src='output.jpg' alt='desc'> | Add alt text. | HTML |
'48' + 35 | 48 + 35 | Avoid string coercion. | JavaScript |
if (index = 44) | if (index == 44) | Use ==. | C++ |
for (count in values) | for (count of values) | for...in iterates keys. | JavaScript |
let item = 'info' | let item = "info" | Double quotes. | Swift |
String name = 'data'; | String name = 'data'; | Correct. | Dart |
<div color=green> | <div style='color:green;'> | Use style attribute. | CSS |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
function bar(z)
print(z)
end | function bar(z)
print(z)
end | Correct. | Lua |
JOIN orders ON orders.id = orders.status | JOIN orders ON orders.id = orders.status | Correct. | SQL |
SELECT COUNT(*) FROM users | SELECT COUNT(*) FROM users; | Missing semicolon. | SQL |
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