0004

Author: ruoru

Algorithms/0004.median-of-two-sorted-arrays/median-of-two-sorted-arrays.rs

@@ -1,43 +1,64 @@
-package problem0004
+use std::cmp;
+use std::mem;
 
-func findMedianSortedArrays(nums1 []int, nums2 []int) float64 {
-	nums := combine(nums1, nums2)
-	return medianOf(nums)
-}
+pub fn median_of_two_sorted_arrays (v1: Vec<i32>, v2: Vec<i32>) -> f32 {
 
-func combine(mis, njs []int) []int {
-	lenMis, i := len(mis), 0
-	lenNjs, j := len(njs), 0
-	res := make([]int, lenMis+lenNjs)
-
-	for k := 0; k < lenMis+lenNjs; k++ {
-		if i == lenMis ||
-			(i < lenMis && j < lenNjs && mis[i] > njs[j]) {
-			res[k] = njs[j]
-			j++
-			continue
-		}
-
-		if j == lenNjs ||
-			(i < lenMis && j < lenNjs && mis[i] <= njs[j]) {
-			res[k] = mis[i]
-			i++
-		}
-	}
-
-	return res
-}
+    let mut vec1 = v1;
+    let mut vec2 = v2;
+
+    if vec1.len() > vec2.len() {
+        mem::swap(&mut vec1, &mut vec2);
+    }
+
+    let len1 = vec1.len();
+    let len2 = vec2.len();
+
+    let half_len = (len1 + len2 + 1) / 2;
+    let mut index_min = 0;
+    let mut index_max = len1;
 
-func medianOf(nums []int) float64 {
-	l := len(nums)
+    while index_min <= index_max {
+        let i = (index_min + index_max) / 2;
+        let j = half_len - i;
 
-	if l == 0 {
-		panic("切片的长度为0，无法求解中位数。")
-	}
+        if i < len1 && vec1[i] < vec2[j - 1] {
+            index_min = i + 1;
+        } else if i > 0 && vec1[i-1] > vec2[j] {
+            index_max = i - 1;
+        } else {
+            let left_max;
+            let right_min;
+            if i == 0 {
+                left_max = vec2[j - 1];
+            } else if j == 0 {
+                left_max = vec1[i-1];
+            } else {
+                left_max = cmp::max(vec1[i-1], vec2[j-1]);
+            }
 
-	if l%2 == 0 {
-		return float64(nums[l/2]+nums[l/2-1]) / 2.0
-	}
+            if (len1 + len2) % 2 == 1 {
+                return left_max as f32;
+            }
 
-	return float64(nums[l/2])
+            if i == len1 {
+                right_min = vec2[j];
+            } else if j == len2 {
+                right_min = vec1[i];
+            } else {
+                right_min = cmp::min(vec1[i], vec2[j]);
+            }
+
+            return (left_max + right_min) as f32 / 2.0
+        }
+    }
+
+    return 0.0;
 }
+
+fn main() {
+    let vec1 = vec![9, 13, 17, 19];
+	let vec2 = vec![2, 7, 9, 14, 15, 24, 28, 38];
+
+    let results = median_of_two_sorted_arrays(vec1, vec2);
+    println!("{}", results);
+}

Algorithms/0004.median-of-two-sorted-arrays/median-of-two-sorted-arrays_test.rs

@@ -1,53 +0,0 @@
-package problem0004
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-type para struct {
-	one []int
-	two []int
-}
-
-type ans struct {
-	one float64
-}
-
-type question struct {
-	p para
-	a ans
-}
-
-func Test_OK(t *testing.T) {
-	ast := assert.New(t)
-
-	qs := []question{
-		question{
-			p: para{
-				one: []int{1, 3},
-				two: []int{2},
-			},
-			a: ans{
-				one: 2,
-			},
-		},
-		question{
-			p: para{
-				one: []int{1, 3},
-				two: []int{2, 4},
-			},
-			a: ans{
-				one: 2.5,
-			},
-		},
-	}
-
-	for _, q := range qs {
-		a, p := q.a, q.p
-		ast.Equal(a.one, findMedianSortedArrays(p.one, p.two), "输入:%v", p)
-	}
-
-	ast.Panics(func() { findMedianSortedArrays([]int{}, []int{}) }, "对空切片求中位数，却没有panic")
-}

README.md

@@ -15,4 +15,5 @@ leetcode in rust lang.
 |:-:|:-|:-:|:-:|:-:|
 |1|[Two Sum](./Algorithms/0001.two-sum)|39%|Easy||
 |2|[Add Two Numbers](./Algorithms/0002.add-two-numbers)|29%|Medium||
-|3|[Longest Substring Without Repeating Characters](./Algorithms/0003.longest-substring-without-repeating-characters)|25%|Medium||
+|3|[Longest Substring Without Repeating Characters](./Algorithms/0003.longest-substring-without-repeating-characters)|25%|Medium||
+|4|[Median of Two Sorted Arrays](./Algorithms/0004.median-of-two-sorted-arrays)|24%|Hard||