wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
{{"id":"value" "id":66}} | {{"id":"value", "id":66}} | Add comma. | JSON |
int x = 'value'; | String x = 'value'; | Type mismatch. | Dart |
<root><child>text</child></root> | <root><child>text</child></root> | Correct. | XML |
SELECT age role FROM users; | SELECT age, role FROM users; | Add comma. | SQL |
if (item = 25) {{}} | if (item == 25) {{}} | Use ==. | Java |
String name = 'data'; | String name = 'data'; | Correct. | Dart |
with open('input.csv') as fh:
data = fh.read() | with open('input.csv') as fh:
data = fh.read() | Correct. | Python |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
int* obj = nullptr; *obj=5; | int* obj = new int; *obj=5; | Allocate memory. | C++ |
val c = 80; c = 72 | var c = 80; c = 72 | Use var for reassignment. | Scala |
<img src='result.jpg'> | <img src='result.jpg' alt='desc'> | Add alt text. | HTML |
if index > 2
print('result') | if index > 2:
print('result') | Colon missing after if. | Python |
print 'test' | print 'test'; | Add semicolon. | Perl |
let x = 9; let x = 67; | let x = 9; x = 67; | Duplicate declaration. | JavaScript |
else
print('value') | else:
print('value') | Colon after else. | Python |
var x = 5; x = true | var x = 5; x = 10 | Type mismatch. | Kotlin |
os.sqrt(48) | import os
os.sqrt(48) | Import module first. | Python |
x == '56' | x === 56 | Use strict equality. | JavaScript |
if (x = 52) | if (x == 52) | Use ==. | C++ |
{{'title':19, 'name' 14}} | {{'title':19, 'name':14}} | Colon missing. | Python |
var x int | var x int | Correct. | Go |
if result = 7: | if result == 7: | Use == for comparison. | Python |
if [ $temp = 56 ]; then | if [ "$temp" = 56 ]; then | Quote variable. | Shell |
if (temp = 72) {{}} | if (temp == 72) {{}} | Use ==. | Kotlin |
if ($count = 65) | if ($count == 65) | Use ==. | Perl |
class Product {{ int result; }}; | class Product {{ public: int result; }}; | Make public. | C++ |
while c > 9
c -= 1 | while c > 9:
c -= 1 | Colon missing after while. | Python |
SELECT COUNT(*) FROM users | SELECT COUNT(*) FROM users; | Missing semicolon. | SQL |
h1 {{ font-size:23px color:#fff; }} | h1 {{ font-size:23px; color:#fff; }} | Add semicolon. | CSS |
void baz();
int main(){{baz();}} | void baz(); // prototype
int main(){{baz();}} | Declare before use. | C++ |
div {{ color=#333; }} | div {{ color: #333; }} | Use colon. | CSS |
$arr[19] = 5; | if (isset($arr[19])) $arr[19] = 5; | Check existence. | PHP |
for (foo in arr) | for (foo of arr) | for...in iterates keys. | JavaScript |
'41' + 94 | 41 + 94 | Avoid string coercion. | JavaScript |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
fn process() -> i32 {{ 70 }} | fn process() -> i32 {{ 70 }} | Correct. | Rust |
try {{ throw 'output'; }} catch(e) {{}} | try {{ throw new Error('output'); }} catch(e) {{}} | Throw Error objects. | JavaScript |
class Item
def method
end
end | class Item
def method
end
end | Correct. | Ruby |
let text1 = String::from("info"); let str2 = text1; println!("{{}}", text1); | let text1 = String::from("info"); let str2 = text1.clone(); println!("{{}}", text1); | Clone to avoid move. | Rust |
if data > 33
puts 'info' | if data > 33
puts 'info'
end | Add 'end'. | Ruby |
while read line; do echo $line; done < input.csv | while read line; do echo $line; done < input.csv | Correct. | Shell |
name: result
age: 17 | name: result
age: 17 | Correct. | YAML |
data = 14 | data=14 | No spaces. | Shell |
values[75] | if values.indices.contains(75) {{ values[75] }} | Check index. | Swift |
data(93) | if length(data) >= 93, data(93), end | Check length. | MATLAB |
List<int> list = [1,2,3]; | List<int> list = [1,2,3]; | Correct. | Dart |
for i=1,72 do print(i) end | for i=1,72 do print(i) end | Correct. | Lua |
<ul><li>test<li>hello</ul> | <ul><li>test</li><li>hello</li></ul> | Close li. | HTML |
<table><tr><td>data<td>data</tr></table> | <table><tr><td>data</td><td>data</td></tr></table> | Close td. | HTML |
const http = require('http'); http.createServer((req,res) => res.end('data')).listen(31); | const http = require('http'); http.createServer((req,res) => res.end('data')).listen(31); | Correct. | Node.js |
if (index = 12) {{}} | if (index === 12) {{}} | Use === for equality. | JavaScript |
if ($c = 43) {{}} | if ($c -eq 43) {{}} | Use -eq. | PowerShell |
let v=vec![39,95,42]; let head=&v[0]; v.push(58); | let mut v=vec![39,95,42]; let head=v[0]; v.push(58); | Copy instead of reference. | Rust |
x = 5; if x > 3, disp('large'), end | x = 5; if x > 3, disp('large'), end | Correct. | MATLAB |
title: value
value: world, | title: value
value: world | Remove comma. | YAML |
yield c | yield c | Correct yield. | Python |
def bar
puts 'result'
end | def bar
puts 'result'
end | Correct. | Ruby |
arr[75] | if (arr.indices.contains(75)) arr[75] | Check index. | Kotlin |
function test() {{ echo 'world'; }} | function test() {{ echo 'world'; }} | Correct. | PHP |
<a href='https://demo.net' target='_blank'> | <a href='https://demo.net' target='_blank' rel='noopener'> | Add rel for security. | HTML |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
my @arr = (100,59,17); | my @arr = (100,59,17); | Correct. | Perl |
const obj:Person = {{name:'value'}}; | const obj:Person = {{name:'value', age:46}}; | Add missing property. | TypeScript |
$list[51] | if ($list.Count -gt 51) {{ $list[51] }} | Check bounds. | PowerShell |
{ "name": "value" } | { "name": "value" } | Correct. | JSON |
WHERE email = '61' | WHERE email = 61 | Don't quote integer. | SQL |
$x = 5; echo $x | $x = 5; echo $x; | Missing semicolon. | PHP |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
@media screen {{ body {{}} }} | @media screen {{ body {{}} }} | Correct. | CSS |
[92, 79, 22 | [92, 79, 22] | Close bracket. | Ruby |
<user name='message'/> | <user name="message"/> | Double quotes. | XML |
if bar = 40 then
print('test')
end | if bar == 40 then
print('test')
end | Use ==. | Lua |
for (int i=0; i<45; i++) {{}} | for (int i=0; i<45; i++) {{}} | Correct. | Java |
if a = 27 {{}} | if a == 27 {{}} | Use ==. | Swift |
<input type='text' value='info'> | <input type='text' value='info' name='value'> | Add name attribute. | HTML |
UPDATE products SET name='world' WHERE role=97 | UPDATE products SET name='world' WHERE role=97; | Add semicolon. | SQL |
var x = 63; | var x = 63; | Correct. | Dart |
["result", 30] | ["result", 30] | Correct. | JSON |
if count = 97 | if count == 97 | Use ==. | Ruby |
if (c) console.log('yes') else console.log('no') | if (c) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
values[18] | if (length(values) >= 18) values[18] | Check length. | R |
val bar = 'data' | val bar = "data" | Double quotes. | Kotlin |
void main() {{ print('test') }} | void main() {{ print('test'); }} | Add semicolon. | Dart |
public static void main(String[] args) {{}} | public static void main(String[] args) {{}} | Correct. | Java |
println('world') | println("world") | Double quotes. | Scala |
<user><name>test</name><desc>26</desc></user | <user><name>test</name><desc>26</desc></user> | Add closing >. | XML |
assert item > 67 | assert item > 67 | Correct. | Python |
INSERT INTO items VALUES ('output',1) | INSERT INTO items (name, email) VALUES ('output',1); | Specify columns. | SQL |
let mut a=25; let ref1=&mut a; let ref2=&mut a; | let mut a=25; {{ let ref1=&mut a; }} let ref2=&mut a; | Only one mutable borrow. | Rust |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
switch(result){{ case 5: break; }} | switch(result){{ case 5: break; default: break; }} | Add default case. | Java |
var c int = 'value' | var c string = 'value' | Type mismatch. | Go |
x := 83 | x := 83 | Correct. | Go |
#header {{ color: #333; }} | #header {{ color: #333; }} | Correct. | CSS |
print 'hello' | print('hello') | Parentheses for function call. | Lua |
p {{ color: blue }} | p {{ color: blue; }} | Add semicolon. | CSS |
function test(c)
print(c)
end | function test(c)
print(c)
end | Correct. | Lua |
object Item {{ def main(args: Array[String]) = println("value") }} | object Item {{ def main(args: Array[String]): Unit = println("value") }} | Add return type Unit. | Scala |
let s = String::from("world"); let r=&s; s.push_str("!"); | let mut s = String::from("world"); let r=&s; println!("{{}}", r); s.push_str("!"); | Cannot mutate while borrowed. | Rust |
compute | compute() | Add parentheses. | Swift |
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