Finish week 1 problem set and merge sort in Rust

py/week_1_set_1.py

@@ -0,0 +1,50 @@
+import matplotlib.pyplot as plt
+import numpy as np
+
+n = np.arange(1, 1000, 1)
+
+# Version 1
+
+a = 2**np.log(n)
+b = 2**2**np.log(n)
+c = n**(5/2)
+d = 2**n**2
+e = (n**2)*np.log(n)
+
+# plt.plot(n, a, 'b', n, b, 'y')  # a < b
+# plt.plot(n, b, 'b', n, c, 'y')  # b > c
+# plt.plot(n, a, 'b', n, c, 'y')  # a < c
+
+# plt.plot(n, c, 'b', n, d, 'y')  # c << d
+# plt.plot(n, c, 'b', n, e, 'y')  # c > e
+# plt.plot(n, e, 'b', n, b, 'y')  # e < b
+# plt.plot(n, e, 'b', n, a, 'y')  # e > a
+
+# a < e < c < b < d
+
+n = np.arange(1, 1000, 1)
+# n = 1000
+a = np.sqrt(n)
+b = 10**n
+c = n**1.5
+d = 2**np.sqrt(np.log(n))
+e = n**5/3
+
+# print(a, b, c, d, e)
+# d < a < c < e < b
+# print(d < a, a < c, c < e, e < b)
+
+plt.plot(n, a, 'b', n, d, 'y') # a > d
+
+plt.show()
+
+"""
+1) n*log(n)
+2) True
+3) Yes if and Sometimes yes
+4) O(nk**2)
+5) :/ Tried:
+
+ecadb
+abecd
+"""

src/main.rs

@@ -1,19 +1,57 @@
-use std::vec::Vec;
 use std::clone::Clone;
+use std::cmp::PartialOrd;
+use std::marker::Copy;
+use std::vec::Vec;
 
+fn merge<T: Clone + PartialOrd + Copy>(a: Vec<T>, b: Vec<T>) -> Vec<T> {
+    let mut r = vec![];
+    let mut i = 0;
+    let mut j = 0;
 
-fn merge_sort<T: Clone>(v: Vec<T>) -> Vec<T> {
-	if v.len() <= 1 {
-		return v;
-	}
-	let sorted = v.to_vec(); 
+    while i < a.len() && j < b.len() {
+        if a[i] < b[j] {
+            r.push(a[i]);
+            i += 1;
+        } else {
+            r.push(b[j]);
+            j += 1;
+        }
+    }
 
-	return sorted;
+    while i < a.len() {
+        r.push(a[i]);
+        i += 1;
+    }
+
+    while j < b.len() {
+        r.push(b[j]);
+        j += 1;
+    }
+
+    return r;
+}
+
+fn merge_sort<T: Clone + PartialOrd + Copy>(v: Vec<T>) -> Vec<T> {
+    if v.len() <= 1 {
+        return v;
+    }
+    let i = v.len() / 2;
+    let a = merge_sort((&v[..i]).to_vec());
+    let b = merge_sort((&v[i..]).to_vec());
+    let r = merge(a, b);
+    return r;
+}
+
+fn mult_bin(a: i64, b: i64) -> i64 {
+    return a * b;
 }
 
 fn main() {
     println!("Hello, world!");
-    let l = vec![2,1,3];
+    let l = vec![4, 2, 1, 3];
     let l = merge_sort(l);
     println!("{:?}", l);
+
+    let r = mult_bin(42, 21);
+    println!("{:?}", r);
 }