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zig : update codes style && rust : add codes for chapter_backtracking. (#613)

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* zig : update codes style

* rust : add codes for chapter_backtracking

* zig : update codes style
This commit is contained in:
sjinzh
2023-07-16 15:36:28 +08:00
committed by GitHub
parent 51a4c5089e
commit ead33ca863
17 changed files with 312 additions and 71 deletions
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32
codes/zig/chapter_dynamic_programming/edit_distance.zig
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@@ -5,7 +5,7 @@
const std = @import("std");
// 编辑距离：暴力搜索
fn edit_distance_dfs(comptime s: []const u8, comptime t: []const u8, i: usize, j: usize) i32 {
fn editDistanceDFS(comptime s: []const u8, comptime t: []const u8, i: usize, j: usize) i32 {
// 若 s 和 t 都为空，则返回 0
if (i == 0 and j == 0) {
return 0;
@@ -20,18 +20,18 @@ fn edit_distance_dfs(comptime s: []const u8, comptime t: []const u8, i: usize, j
}
// 若两字符相等，则直接跳过此两字符
if (s[i - 1] == t[j - 1]) {
return edit_distance_dfs(s, t, i - 1, j - 1);
return editDistanceDFS(s, t, i - 1, j - 1);
}
// 最少编辑步数 = 插入、删除、替换这三种操作的最少编辑步数 + 1
var insert = edit_distance_dfs(s, t, i, j - 1);
var delete = edit_distance_dfs(s, t, i - 1, j);
var replace = edit_distance_dfs(s, t, i - 1, j - 1);
var insert = editDistanceDFS(s, t, i, j - 1);
var delete = editDistanceDFS(s, t, i - 1, j);
var replace = editDistanceDFS(s, t, i - 1, j - 1);
// 返回最少编辑步数
return @min(@min(insert, delete), replace) + 1;
}
// 编辑距离：记忆化搜索
fn edit_distance_dfs_mem(comptime s: []const u8, comptime t: []const u8, mem: anytype, i: usize, j: usize) i32 {
fn editDistanceDFSMem(comptime s: []const u8, comptime t: []const u8, mem: anytype, i: usize, j: usize) i32 {
// 若 s 和 t 都为空，则返回 0
if (i == 0 and j == 0) {
return 0;
@@ -50,19 +50,19 @@ fn edit_distance_dfs_mem(comptime s: []const u8, comptime t: []const u8, mem: an
}
// 若两字符相等，则直接跳过此两字符
if (s[i - 1] == t[j - 1]) {
return edit_distance_dfs_mem(s, t, mem, i - 1, j - 1);
return editDistanceDFSMem(s, t, mem, i - 1, j - 1);
}
// 最少编辑步数 = 插入、删除、替换这三种操作的最少编辑步数 + 1
var insert = edit_distance_dfs_mem(s, t, mem, i, j - 1);
var delete = edit_distance_dfs_mem(s, t, mem, i - 1, j);
var replace = edit_distance_dfs_mem(s, t, mem, i - 1, j - 1);
var insert = editDistanceDFSMem(s, t, mem, i, j - 1);
var delete = editDistanceDFSMem(s, t, mem, i - 1, j);
var replace = editDistanceDFSMem(s, t, mem, i - 1, j - 1);
// 记录并返回最少编辑步数
mem[i][j] = @min(@min(insert, delete), replace) + 1;
return mem[i][j];
}
// 编辑距离：动态规划
fn edit_distance_dp(comptime s: []const u8, comptime t: []const u8) i32 {
fn editDistanceDP(comptime s: []const u8, comptime t: []const u8) i32 {
comptime var n = s.len;
comptime var m = t.len;
var dp = [_][m + 1]i32{[_]i32{0} ** (m + 1)} ** (n + 1);
@@ -89,7 +89,7 @@ fn edit_distance_dp(comptime s: []const u8, comptime t: []const u8) i32 {
}
// 编辑距离：状态压缩后的动态规划
fn edit_distance_dp_comp(comptime s: []const u8, comptime t: []const u8) i32 {
fn editDistanceDPComp(comptime s: []const u8, comptime t: []const u8) i32 {
comptime var n = s.len;
comptime var m = t.len;
var dp = [_]i32{0} ** (m + 1);
@@ -126,20 +126,20 @@ pub fn main() !void {
comptime var m = t.len;
// 暴力搜索
var res = edit_distance_dfs(s, t, n, m);
var res = editDistanceDFS(s, t, n, m);
std.debug.print("将 {s} 更改为 {s} 最少需要编辑 {} 步\n", .{ s, t, res });
// 记忆搜索
var mem = [_][m + 1]i32{[_]i32{-1} ** (m + 1)} ** (n + 1);
res = edit_distance_dfs_mem(s, t, @constCast(&mem), n, m);
res = editDistanceDFSMem(s, t, @constCast(&mem), n, m);
std.debug.print("将 {s} 更改为 {s} 最少需要编辑 {} 步\n", .{ s, t, res });
// 动态规划
res = edit_distance_dp(s, t);
res = editDistanceDP(s, t);
std.debug.print("将 {s} 更改为 {s} 最少需要编辑 {} 步\n", .{ s, t, res });
// 状态压缩后的动态规划
res = edit_distance_dp_comp(s, t);
res = editDistanceDPComp(s, t);
std.debug.print("将 {s} 更改为 {s} 最少需要编辑 {} 步\n", .{ s, t, res });
_ = try std.io.getStdIn().reader().readByte();