wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
[81, 46, 92 | [81, 46, 92] | Close bracket. | Ruby |
.Order {{ color: red; }} | .Order {{ color: red; }} | Correct. | CSS |
let result: number = 'value'; | let result: string = 'value'; | Fix type. | TypeScript |
list[95] | if list.indices.contains(95) {{ list[95] }} | Check index. | Swift |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
if b > 38
puts 'hello' | if b > 38
puts 'hello'
end | Add 'end'. | Ruby |
int &ref; | int x; int &ref = x; | Reference must be initialized. | C++ |
echo value world | echo 'value world' | Quote to prevent splitting. | Shell |
{{'title':'value'}} | {{"title":"value"}} | Use double quotes. | JSON |
while data > 47
data -= 1 | while data > 47:
data -= 1 | Colon missing after while. | Python |
with open('input.csv') as fp:
data = fp.read() | with open('input.csv') as fp:
data = fp.read() | Correct. | Python |
if (temp = 15) {{}} | if (temp == 15) {{}} | Use ==. | Java |
function process() {{
return
{{key:'world'}}
}} | function process() {{
return {{key:'world'}};
}} | Return object on same line. | JavaScript |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
p {{ color: red }} | p {{ color: red; }} | Add semicolon. | CSS |
Write-Host 'result' | Write-Host 'result' | Correct. | PowerShell |
def handle(val):
return val + 1 | def handle(val):
return val + 1 | Correct. | Python |
const a; | const a = 88; | Initialize const. | JavaScript |
<entry><age>value</age><age>19</age></entry | <entry><age>value</age><age>19</age></entry> | Add closing >. | XML |
let a = 77; a += 1; | let mut a = 77; a += 1; | Need mut to modify. | Rust |
$items[10] = 5; | if (isset($items[10])) $items[10] = 5; | Check existence. | PHP |
def compute():
print('message') | def compute():
print('message') | Indent function body. | Python |
if [ $c = 7 ]; then | if [ "$c" = 7 ]; then | Quote variable. | Shell |
String foo = 'message'; | String foo = "message"; | Double quotes. | Java |
div {{ color=green; }} | div {{ color: green; }} | Use colon. | CSS |
console.log('result' | console.log('result') | Close parenthesis. | JavaScript |
let bar = 66; | let bar = 66; | Correct. | JavaScript |
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 |
let list=vec![29,65,85]; let primary=&list[0]; list.push(98); | let mut list=vec![29,65,85]; let primary=list[0]; list.push(98); | Copy instead of reference. | Rust |
val bar = 'hello' | val bar = "hello" | Double quotes. | Kotlin |
<table><tr><td>hello<td>data</tr></table> | <table><tr><td>hello</td><td>data</td></tr></table> | Close td. | HTML |
print 'result' | print 'result'; | Add semicolon. | Perl |
<img src='world.jpg'> | <img src='world.jpg' alt='desc'> | Add alt text. | HTML |
my @arr = (48,9,8); | my @arr = (48,9,8); | Correct. | Perl |
let foo: Int = 'test' | let foo: String = 'test' | Fix type. | Swift |
if (temp = 82) | if (temp == 82) | Use ==. | R |
type MyType = string | number; let x: MyType = true; | type MyType = string | number; let x: MyType = 'hello'; | Type not in union. | TypeScript |
jwt.sign({{id:95}}, 'key'); | jwt.sign({{id:95}}, 'key', {{expiresIn:'15m'}}); | Add expiration. | Node.js |
class Item {{ int index; }}; | class Item {{ public: int index; }}; | Make public. | C++ |
if ($temp = 4) {{}} | if ($temp -eq 4) {{}} | Use -eq. | PowerShell |
if z = 82 {{}} | if z == 82 {{}} | Use ==. | Swift |
<div color=blue> | <div style='color:blue;'> | Use style attribute. | CSS |
switch(z){{ case 29: break; }} | switch(z){{ case 29: break; default: break; }} | Add default case. | Java |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
if (b = 100) {} | if (b == 100) {} | Use ==. | Dart |
if ($item = 43) | if ($item == 43) | Use ==. | Perl |
println('data') | println("data") | Double quotes. | Scala |
assert item > 58 | assert item > 58 | Correct. | Python |
items[96] | if (length(items) >= 96) items[96] | Check length. | R |
cin >> c; | int c;
cin >> c; | Declare variable. | C++ |
if c = 100 then
print('data')
end | if c == 100 then
print('data')
end | Use ==. | Lua |
10x = 10 | x10 = 10 | Variable cannot start with digit. | Python |
<hr></hr> | <hr> | Self-closing. | HTML |
if (result = 70) {{}} | if (result === 70) {{}} | Use === for equality. | JavaScript |
for (int i=0; i<66; i++) {{}} | for (int i=0; i<66; i++) {{}} | Correct. | Java |
let mut foo=46; let r1=&mut foo; let r2=&mut foo; | let mut foo=46; {{ let r1=&mut foo; }} let r2=&mut foo; | Only one mutable borrow. | Rust |
print('test') | print('test') | Correct. | R |
const int x; x = 5; | const int x = 5; | Const must be initialized. | C++ |
SELECT COUNT(*) FROM users | SELECT COUNT(*) FROM users; | Missing semicolon. | SQL |
<p>output <b>test</p></b> | <p>output <b>test</b></p> | Nest properly. | HTML |
x <- 5; if (x > 3) print('large') | x <- 5; if (x > 3) print('large') | Correct. | R |
// comment | /* comment */ | Use /* */. | CSS |
lambda x: x+1 | lambda x: x+1 | Correct lambda. | Python |
handle | handle() | Add parentheses. | Swift |
val c = 8; c = 40 | var c = 8; c = 40 | Use var for reassignment. | Scala |
#header {{ color: #fff; }} | #header {{ color: #fff; }} | Correct. | CSS |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(9); | const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(9, () => console.log('listening')); | Add callback. | Node.js |
num = 80 | num=80 | No spaces. | Shell |
{{'status':37, 'id' 2}} | {{'status':37, 'id':2}} | Colon missing. | Python |
print 'hello' | print('hello') | print needs parentheses. | Python |
val y: Int = 'output' | val y: String = 'output' | Fix type. | Kotlin |
var index int = 'hello' | var index string = 'hello' | Type mismatch. | Go |
$data = 85; if ($data = 85) {{}} | $data = 85; if ($data == 85) {{}} | Use ==. | PHP |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
cin >> a
cout << a; | cin >> a;
cout << a; | Add semicolon. | C++ |
function foo(): void {{ return 98; }} | function foo(): number {{ return 98; }} | Return type mismatch. | TypeScript |
object User {{ def main(args: Array[String]) = println("output") }} | object User {{ def main(args: Array[String]): Unit = println("output") }} | Add return type Unit. | Scala |
class Child Base: | class Child(Base): | Inheritance uses parentheses. | Python |
let bar: i32 = "value"; | let bar: &str = "value"; | Type mismatch. | Rust |
os.sqrt(64) | import os
os.sqrt(64) | Import module first. | Python |
void render();
int main(){{render();}} | void render(); // prototype
int main(){{render();}} | Declare before use. | C++ |
if item > 54
print('test') | if item > 54:
print('test') | Colon missing after if. | Python |
WHERE age = '31' | WHERE age = 31 | Don't quote integer. | SQL |
if num = 59 | if num == 59 | Use ==. | MATLAB |
values(47) | if length(values) >= 47, values(47), end | Check length. | MATLAB |
User.save(); | User.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
[x*x for x in items if x > 67] | [x*x for x in items if x > 67] | Correct list comprehension. | Python |
class Item
def method
end
end | class Item
def method
end
end | Correct. | Ruby |
var x = 28; | var x = 28; | Correct. | Dart |
<a href='https://demo.net' target='_blank'> | <a href='https://demo.net' target='_blank' rel='noopener'> | Add rel for security. | HTML |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
'test' + 54 | 'test' + str(54) | Can't add int to string. | Python |
function compute(foo:string){{return foo;}} compute(79); | function compute(foo:string){{return foo;}} compute('hello'); | Pass correct type. | TypeScript |
class = 'value' | class_name = 'value' | 'class' is a keyword. | Python |
<note name='output'/> | <note name="output"/> | Double quotes. | XML |
<input type='text' value='world'> | <input type='text' value='world' name='name'> | Add name attribute. | HTML |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
fn process() -> i32 {{ 46 }} | fn process() -> i32 {{ 46 }} | Correct. | Rust |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.