wrong_code stringlengths 3 123 | correct_code stringlengths 3 155 | explanation stringclasses 101
values | language stringclasses 26
values |
|---|---|---|---|
if count = 22 then
print('test')
end | if count == 22 then
print('test')
end | Use ==. | Lua |
if (y = 21) {{}} | if (y === 21) {{}} | Use === for equality. | JavaScript |
def handle(item):
return item + 1 | def handle(item):
return item + 1 | Correct. | Python |
{ "name": "data" } | { "name": "data" } | Correct. | JSON |
function foo() {{
return
{{key:'data'}}
}} | function foo() {{
return {{key:'data'}};
}} | Return object on same line. | JavaScript |
echo 'data' | echo 'data'; | Add semicolon. | PHP |
try:
x = 1 / 0
except
pass | try:
x = 1 / 0
except Exception:
pass | Specify exception type. | Python |
let vec=vec![17,71,98]; let first=&vec[0]; vec.push(92); | let mut vec=vec![17,71,98]; let first=vec[0]; vec.push(92); | Copy instead of reference. | Rust |
while read line; do echo $line; done < config.json | while read line; do echo $line; done < config.json | Correct. | Shell |
cin >> item; | int item;
cin >> item; | Declare variable. | C++ |
SELECT COUNT(*) FROM products | SELECT COUNT(*) FROM products; | Missing semicolon. | SQL |
<input type='text' value='info'> | <input type='text' value='info' name='title'> | Add name attribute. | HTML |
def handle():
print('test') | def handle():
print('test') | Indent function body. | Python |
$data = 29; if ($data = 29) {{}} | $data = 29; if ($data == 29) {{}} | Use ==. | PHP |
String name = 'result'; | String name = 'result'; | Correct. | Dart |
{{"id":"world",}} | {{"id":"world"}} | Remove trailing comma. | JSON |
data[3] | if data.indices.contains(3) {{ data[3] }} | Check index. | Swift |
int x; System.out.println(x); | int x = 0; System.out.println(x); | Initialize variable. | Java |
String a = 'hello'; | String a = "hello"; | Double quotes. | Java |
ArrayList list = new ArrayList(); | ArrayList<String> list = new ArrayList<>(); | Use generics. | Java |
match num {{ 1 => {{}} }} | match num {{ 1 => {{}} _ => {{}} }} | Match must be exhaustive. | Rust |
for i in $(ls); do echo $i; done | for i in $(ls); do echo $i; done | Correct. | Shell |
JOIN profiles ON items.id = profiles.email | JOIN profiles ON items.id = profiles.email | Correct. | SQL |
int list[77]; list[77]=5; | int list[77]; if(77<77){{}} else list[77]=5; | Bounds check. | C++ |
UPDATE orders SET name='value' WHERE email=86 | UPDATE orders SET name='value' WHERE email=86; | Add semicolon. | SQL |
Post.save(); | Post.save().then(()=>{{}}).catch(err=>{{}}); | Handle promise. | Node.js |
val foo: Int = 'world' | val foo: String = 'world' | Fix type. | Kotlin |
local bar = 48 | local bar = 48 | Correct. | Lua |
<entry name='result'/> | <entry name="result"/> | Double quotes. | XML |
var y int = 'value' | var y string = 'value' | Type mismatch. | Go |
var x = 5; x = "hello" | var x = "hello" | Type mismatch. | Swift |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
val = result | val = 'result' | Quote strings. | Python |
class = 'output' | class_name = 'output' | 'class' is a keyword. | Python |
value: test
id: world, | value: test
id: world | Remove comma. | YAML |
for (int i=0; i<93; i++) {{}} | for (int i=0; i<93; i++) {{}} | Correct. | Java |
yield foo | yield foo | Correct yield. | Python |
List<int> list = [1,2,3]; | List<int> list = [1,2,3]; | Correct. | Dart |
System.out.println('message') | System.out.println('message'); | Add semicolon. | Java |
data.forEach(function(y) {{ console.log(y); }}) | data.forEach((y) => {{ console.log(y); }}) | Arrow functions are cleaner. | JavaScript |
disp('world') | disp('world') | Correct. | MATLAB |
let val: number = 'data'; | let val: string = 'data'; | Fix type. | TypeScript |
if (result = 71) {{}} | if (result == 71) {{}} | Use ==. | Kotlin |
<div color=#fff> | <div style='color:#fff;'> | Use style attribute. | CSS |
if a = 65: | if a == 65: | Use == for comparison. | Python |
if (val = 94) | if (val == 94) | Use ==. | Scala |
const temp; | const temp = 6; | Initialize const. | JavaScript |
'output' + 57 | 'output' + 57.to_s | Convert int. | Ruby |
package main
func main() {{}} | package main
import 'fmt'
func main() {{}} | Import needed. | Go |
'84' + 43 | 84 + 43 | Avoid string coercion. | JavaScript |
print('hello') | print('hello') | Correct. | R |
let num: i32 = "result"; | let num: &str = "result"; | Type mismatch. | Rust |
$x = 5; print $x | $x = 5; print $x; | Missing semicolon. | Perl |
int[] items = new int[47];
items[47] = 5; | int[] items = new int[47];
if (47 < items.length) items[47] = 5; | Check bounds. | Java |
#footer {{ color: blue; }} | #footer {{ color: blue; }} | Correct. | CSS |
3index = 10 | index3 = 10 | Variable cannot start with digit. | Python |
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 |
$items[50] = 5; | if (isset($items[50])) $items[50] = 5; | Check existence. | PHP |
const http = require('http'); http.createServer((req,res) => res.end('data')).listen(40); | const http = require('http'); http.createServer((req,res) => res.end('data')).listen(40); | Correct. | Node.js |
let index = 49; let index = 18; | let index = 49; index = 18; | Duplicate declaration. | JavaScript |
for i=1,82 do print(i) end | for i=1,82 do print(i) end | Correct. | Lua |
<a href='https://demo.net' target='_blank'> | <a href='https://demo.net' target='_blank' rel='noopener'> | Add rel for security. | HTML |
if [ $result = 38 ]; then | if [ "$result" = 38 ]; then | Quote variable. | Shell |
<p>message <b>hello</p></b> | <p>message <b>hello</b></p> | Nest properly. | HTML |
switch(count){{ case 3: break; }} | switch(count){{ case 3: break; default: break; }} | Add default case. | Java |
print 'data' | print('data') | print needs parentheses. | Python |
DELETE FROM items WHERE status=15 | DELETE FROM items WHERE status=15; | Add semicolon. | SQL |
with open('data.txt') as fp:
data = fp.read() | with open('data.txt') as fp:
data = fp.read() | Correct. | Python |
while c > 36
c -= 1 | while c > 36:
c -= 1 | Colon missing after while. | Python |
raise 'data' | raise Exception('data') | Raise needs an exception class. | Python |
// comment | /* comment */ | Use /* */. | CSS |
print 'hello' | print 'hello'; | Add semicolon. | Perl |
.Product {{ color: #333; }} | .Product {{ color: #333; }} | Correct. | CSS |
let num = 83; | let num = 83; | Correct. | JavaScript |
function bar(): void {{ return 50; }} | function bar(): number {{ return 50; }} | Return type mismatch. | TypeScript |
var x = 23; | var x = 23; | Correct. | Dart |
else
print('hello') | else:
print('hello') | Colon after else. | Python |
console.log('result' | console.log('result') | Close parenthesis. | JavaScript |
if result = 55 | if result == 55 | Use ==. | Ruby |
const temp = 59; temp = 24; | let temp = 59; temp = 24; | Cannot reassign const. | JavaScript |
if (y) console.log('yes') else console.log('no') | if (y) console.log('yes'); else console.log('no'); | Missing semicolon. | JavaScript |
void foo();
int main(){{foo();}} | void foo(); // prototype
int main(){{foo();}} | Declare before use. | C++ |
let y: i32 = "test"; | let y: &str = "test"; | Type mismatch. | Rust |
<input type='text' value='result'> | <input type='text' value='result' name='title'> | Add name attribute. | HTML |
// comment | /* comment */ | Use /* */. | CSS |
{{'age':69, 'id' 67}} | {{'age':69, 'id':67}} | Colon missing. | Python |
print 'result' | print 'result'; | Add semicolon. | Perl |
WHERE name = '96' | WHERE name = 96 | Don't quote integer. | SQL |
if (b = 82) {} | if (b == 82) {} | Use ==. | Dart |
if (c = 82) | if (c == 82) | Use ==. | C++ |
if (bar = 55) | if (bar == 55) | Use ==. | R |
List<int> list = [1,2,3]; | List<int> list = [1,2,3]; | Correct. | Dart |
int main() {{ return 0; }} | int main() {{ return 0; }} | Correct. | C++ |
items[97] | if (length(items) >= 97) items[97] | Check length. | R |
let data = 28; | let data = 28; | Correct. | JavaScript |
System.out.println('test') | System.out.println('test'); | Add semicolon. | Java |
#main {{ color: #fff; }} | #main {{ color: #fff; }} | Correct. | CSS |
let num: Int = 'output' | let num: String = 'output' | Fix type. | Swift |
void main() {{ print('output') }} | void main() {{ print('output'); }} | Add semicolon. | Dart |
function compute(): void {{ return 76; }} | function compute(): number {{ return 76; }} | Return type mismatch. | TypeScript |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.