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Retranslate the complete English edition from Simplified Chinese (#2010)

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* Retranslate the complete English edition from Simplified Chinese

* Polish three English explanations after reader-focused review
This commit is contained in:
Yudong Jin
2026-10-31 03:35:51 +08:00
committed by GitHub
parent ef46e2ed95
commit 14c314c08c
1502 changed files with 29459 additions and 23517 deletions
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66
en/codes/javascript/chapter_dynamic_programming/edit_distance.js
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@@ -4,76 +4,76 @@
* Author: Gaofer Chou (gaofer-chou@qq.com)
*/
/* Edit distance: Brute-force search */
/* Edit distance: brute-force search */
function editDistanceDFS(s, t, i, j) {
// If both s and t are empty, return 0
// If the current prefixes of both s and t are empty, return 0
if (i === 0 && j === 0) return 0;
// If s is empty, return length of t
// If the current prefix of s is empty, return the current prefix length j of t
if (i === 0) return j;
// If t is empty, return length of s
// If the current prefix of t is empty, return the current prefix length i of s
if (j === 0) return i;
// If two characters are equal, skip both characters
// If the two characters are equal, skip both of them
if (s.charAt(i - 1) === t.charAt(j - 1))
return editDistanceDFS(s, t, i - 1, j - 1);
// Minimum edit steps = minimum edit steps of insert, delete, replace + 1
// Minimum edits = the minimum among the insertion, deletion, and replacement subproblems + 1
const insert = editDistanceDFS(s, t, i, j - 1);
const del = editDistanceDFS(s, t, i - 1, j);
const replace = editDistanceDFS(s, t, i - 1, j - 1);
// Return minimum edit steps
// Return the minimum number of edits
return Math.min(insert, del, replace) + 1;
}
/* Edit distance: Memoization search */
/* Edit distance: memoized search */
function editDistanceDFSMem(s, t, mem, i, j) {
// If both s and t are empty, return 0
// If the current prefixes of both s and t are empty, return 0
if (i === 0 && j === 0) return 0;
// If s is empty, return length of t
// If the current prefix of s is empty, return the current prefix length j of t
if (i === 0) return j;
// If t is empty, return length of s
// If the current prefix of t is empty, return the current prefix length i of s
if (j === 0) return i;
// If there's a record, return it directly
// If a result has already been recorded, return it directly
if (mem[i][j] !== -1) return mem[i][j];
// If two characters are equal, skip both characters
// If the two characters are equal, skip both of them
if (s.charAt(i - 1) === t.charAt(j - 1))
return editDistanceDFSMem(s, t, mem, i - 1, j - 1);
// Minimum edit steps = minimum edit steps of insert, delete, replace + 1
// Minimum edits = the minimum among the insertion, deletion, and replacement subproblems + 1
const insert = editDistanceDFSMem(s, t, mem, i, j - 1);
const del = editDistanceDFSMem(s, t, mem, i - 1, j);
const replace = editDistanceDFSMem(s, t, mem, i - 1, j - 1);
// Record and return minimum edit steps
// Record and return the minimum number of edits
mem[i][j] = Math.min(insert, del, replace) + 1;
return mem[i][j];
}
/* Edit distance: Dynamic programming */
/* Edit distance: dynamic programming */
function editDistanceDP(s, t) {
const n = s.length,
m = t.length;
const dp = Array.from({ length: n + 1 }, () => new Array(m + 1).fill(0));
// State transition: first row and first column
// State transitions: first row and first column
for (let i = 1; i <= n; i++) {
dp[i][0] = i;
}
for (let j = 1; j <= m; j++) {
dp[0][j] = j;
}
// State transition: rest of the rows and columns
// State transitions: remaining rows and columns
for (let i = 1; i <= n; i++) {
for (let j = 1; j <= m; j++) {
if (s.charAt(i - 1) === t.charAt(j - 1)) {
// If two characters are equal, skip both characters
// If the two characters are equal, skip both of them
dp[i][j] = dp[i - 1][j - 1];
} else {
// Minimum edit steps = minimum edit steps of insert, delete, replace + 1
// Minimum edits = the minimum among the insertion, deletion, and replacement subproblems + 1
dp[i][j] =
Math.min(dp[i][j - 1], dp[i - 1][j], dp[i - 1][j - 1]) + 1;
}
@@ -82,31 +82,31 @@ function editDistanceDP(s, t) {
return dp[n][m];
}
/* Edit distance: Space-optimized dynamic programming */
/* Edit distance: space-optimized dynamic programming */
function editDistanceDPComp(s, t) {
const n = s.length,
m = t.length;
const dp = new Array(m + 1).fill(0);
// State transition: first row
// State transitions: first row
for (let j = 1; j <= m; j++) {
dp[j] = j;
}
// State transition: rest of the rows
// State transitions: remaining rows
for (let i = 1; i <= n; i++) {
// State transition: first column
// State transitions: first column
let leftup = dp[0]; // Temporarily store dp[i-1, j-1]
dp[0] = i;
// State transition: rest of the columns
// State transitions: remaining columns
for (let j = 1; j <= m; j++) {
const temp = dp[j];
if (s.charAt(i - 1) === t.charAt(j - 1)) {
// If two characters are equal, skip both characters
// If the two characters are equal, skip both of them
dp[j] = leftup;
} else {
// Minimum edit steps = minimum edit steps of insert, delete, replace + 1
// Minimum edits = the minimum among the insertion, deletion, and replacement subproblems + 1
dp[j] = Math.min(dp[j - 1], dp[j], leftup) + 1;
}
leftup = temp; // Update for next round's dp[i-1, j-1]
leftup = temp; // Update to dp[i-1, j-1] for the next iteration
}
}
return dp[m];
@@ -119,17 +119,17 @@ const n = s.length,
// Brute-force search
let res = editDistanceDFS(s, t, n, m);
console.log(`Changing ${s} to ${t} requires minimum ${res} edits`);
console.log(`Minimum number of edits to transform ${s} into ${t}: ${res}`);
// Memoization search
// Memoized search
const mem = Array.from(new Array(n + 1), () => new Array(m + 1).fill(-1));
res = editDistanceDFSMem(s, t, mem, n, m);
console.log(`Changing ${s} to ${t} requires minimum ${res} edits`);
console.log(`Minimum number of edits to transform ${s} into ${t}: ${res}`);
// Dynamic programming
res = editDistanceDP(s, t);
console.log(`Changing ${s} to ${t} requires minimum ${res} edits`);
console.log(`Minimum number of edits to transform ${s} into ${t}: ${res}`);
// Space-optimized dynamic programming
res = editDistanceDPComp(s, t);
console.log(`Changing ${s} to ${t} requires minimum ${res} edits`);
console.log(`Minimum number of edits to transform ${s} into ${t}: ${res}`);