rust-algorithm-change — human mapping

This mapping has 3 multi-map groups: several pairings are equally correct there. The code view shows one arbitrary valid pairing, not the only one.

This mapping has 3 all-to-all groups: every node on one side corresponds to every node on the other, and none is deleted or inserted. Each member carries an all N:M badge; selecting one highlights all of its counterparts, in the tree and in the code view alike.

A painting is a person's account of this edit as text, recorded independently of the node mapping - a rendering often has several equally defensible answers where the mapping has one. Deletions and insertions carry no position on the opposite side in a painting, so that panel draws no caret for them.

Before1fn find_duplicate(nums: &[i32]) -> Option<i32> {
2    // Brute force approach
3    for i in 0..nums.len() {
4        for j in i+1..nums.len() {
5            if nums[i] == nums[j] {
6                return Some(nums[i]);
7            }
8        }
9    }
10    None
11}
12
13fn main() {
14    let nums = vec![1, 3, 4, 2, 2];
15    if let Some(dup) = find_duplicate(&nums) {
…lines 16–20 unchanged (5 lines)

After1use std::collections::HashSet;
2
3fn find_duplicate(nums: &[i32]) -> Option<i32> {
4    // HashSet approach - O(n) time complexity
5    let mut seen = HashSet::new();
6    
7    for &num in nums {
8        if seen.contains(&num) {
9            return Some(num);
10        }
11        seen.insert(num);
12    }
13    
14    None
15}
16
17fn main() {
18    let nums = vec![1, 3, 4, 2, 2];
…lines 19–24 unchanged (6 lines)

Before1fn find_duplicate(nums: &[i32]) -> Option<i32> {
2    // Brute force approach
3    for i in 0..nums.len() {
4        for j in i+1..nums.len() {
5            if nums[i] == nums[j] {
6                return Some(nums[i]);
7            }
8        }
9    }
10    None
11}
12
13fn main() {
14    let nums = vec![1, 3, 4, 2, 2];
15    if let Some(dup) = find_duplicate(&nums) {
…lines 16–20 unchanged (5 lines)

After1use std::collections::HashSet;
2
3fn find_duplicate(nums: &[i32]) -> Option<i32> {
4    // HashSet approach - O(n) time complexity
5    let mut seen = HashSet::new();
6    
7    for &num in nums {
8        if seen.contains(&num) {
9            return Some(num);
10        }
11        seen.insert(num);
12    }
13    
14    None
15}
16
17fn main() {
18    let nums = vec![1, 3, 4, 2, 2];
…lines 19–24 unchanged (6 lines)

Before1fn find_duplicate(nums: &[i32]) -> Option<i32> {
2    // Brute force approach
3    for i in 0..nums.len() {
4        for j in i+1..nums.len() {
5            if nums[i] == nums[j] {
6                return Some(nums[i]);
7            }
8        }
9    }
10    None
11}
12
13fn main() {
14    let nums = vec![1, 3, 4, 2, 2];
15    if let Some(dup) = find_duplicate(&nums) {
…lines 16–20 unchanged (5 lines)

After1use std::collections::HashSet;
2
3fn find_duplicate(nums: &[i32]) -> Option<i32> {
4    // HashSet approach - O(n) time complexity
5    let mut seen = HashSet::new();
6    
7    for &num in nums {
8        if seen.contains(&num) {
9            return Some(num);
10        }
11        seen.insert(num);
12    }
13    
14    None
15}
16
17fn main() {
18    let nums = vec![1, 3, 4, 2, 2];
…lines 19–24 unchanged (6 lines)

Before

source_file

function_item

fn "fn"

identifier "find_duplicate"

parameters

( "("

parameter

identifier "nums"

: ":"

reference_type

& "&"

array_type

[ "["

primitive_type "i32"

] "]"

) ")"

-> "->"

generic_type

type_identifier "Option"

type_arguments

< "<"

primitive_type "i32"

> ">"

block

{ "{"

line_comment

// "//"

expression_statement any 2:1

for_expression any 2:1

for "for" all 2:1

identifier "i"

in "in"

range_expression

integer_literal "0"

.. ".."

call_expression

field_expression

identifier "nums"

. "."

field_identifier "len"

arguments

( "("

) ")"

block any 2:1

{ "{" all 2:1

expression_statement any 2:1

for_expression any 2:1

for "for" all 2:1

identifier "j"

in "in"

range_expression

binary_expression

identifier "i"

+ "+"

integer_literal "1"

.. ".."

call_expression

field_expression

identifier "nums"

. "."

field_identifier "len"

arguments

( "("

) ")"

block any 2:1

{ "{" all 2:1

expression_statement

if_expression

if "if"

binary_expression

index_expression

identifier "nums"

[ "["

identifier "i"

] "]"

== "=="

index_expression

identifier "nums"

[ "["

identifier "j"

] "]"

block

{ "{"

expression_statement

return_expression

return "return"

call_expression

identifier "Some"

arguments

( "("

index_expression

identifier "nums"

[ "["

identifier "i"

] "]"

) ")"

; ";"

} "}"

} "}" all 2:1

identifier "None"

} "}"

function_item (+82 nodes collapsed)

After

source_file

use_declaration

use "use"

scoped_identifier

identifier "std"

:: "::"

identifier "collections"

:: "::"

identifier "HashSet"

; ";"

function_item

fn "fn"

identifier "find_duplicate"

parameters

( "("

parameter

identifier "nums"

: ":"

reference_type

& "&"

array_type

[ "["

primitive_type "i32"

] "]"

) ")"

-> "->"

generic_type

type_identifier "Option"

type_arguments

< "<"

primitive_type "i32"

> ">"

block

{ "{"

line_comment

// "//"

let_declaration

let "let"

mutable_specifier "mut"

identifier "seen"

= "="

call_expression

scoped_identifier

identifier "HashSet"

:: "::"

identifier "new"

arguments

( "("

) ")"

; ";"

expression_statement any 2:1

for_expression any 2:1

for "for" all 2:1

reference_pattern

& "&"

identifier "num"

in "in"

identifier "nums"

block any 2:1

{ "{" all 2:1

expression_statement

if_expression

if "if"

call_expression

field_expression

identifier "seen"

. "."

field_identifier "contains"

arguments

( "("

reference_expression

& "&"

identifier "num"

) ")"

block

{ "{"

expression_statement

return_expression

return "return"

call_expression

identifier "Some"

arguments

( "("

identifier "num"

) ")"

; ";"

} "}"

expression_statement

call_expression

field_expression

identifier "seen"

. "."

field_identifier "insert"

arguments

( "("

identifier "num"

) ")"

; ";"

} "}" all 2:1

identifier "None"

} "}"

function_item (+82 nodes collapsed)

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