first commit

Author: AceCoooool

README.md

@@ -1,2 +1,3 @@
 # algs4cplusplus
 Algorithms, 4th edition textbook code (using c++)
+

ch1/1_BinarySearch/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.8)
+project(1_BinarySearch)
+
+set(CMAKE_CXX_STANDARD 14)
+
+set(SOURCE_FILES main.cpp)
+add_executable(1_BinarySearch ${SOURCE_FILES})

ch1/1_BinarySearch/main.cpp

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+#include <iostream>
+#include <vector>
+#include <fstream>
+#include <algorithm>
+
+using namespace std;
+
+/**
+* Returns the index of the specified key in the specified array.
+*
+* @param  a the array of integers, must be sorted in ascending order
+* @param  key the search key
+* @return index of key in array {@code a} if present; {@code -1} otherwise
+*/
+int indexOf(vector<int> &a, int key) {
+    int lo = 0, hi = a.size() - 1;
+    while (lo <= hi) {
+        // Key is in a[lo..hi] or not present.
+        int mid = lo + (hi - lo) / 2;
+        if (key < a[mid]) hi = mid - 1;
+        else if (key > a[mid]) lo = mid + 1;
+        else return mid;
+    }
+    return -1;
+}
+
+int main() {
+    // TODO: change to relative path
+    ifstream input("/home/ace/AceDev/C++/algorithm/ch1/1_BinarySearch/tinyW.txt");
+    vector<int> whitelist;
+    int t;
+    while (input >> t) {
+        whitelist.push_back(t);
+    }
+    sort(whitelist.begin(), whitelist.end());
+    ifstream check("/home/ace/AceDev/C++/algorithm/ch1/1_BinarySearch/tinyT.txt");
+    while (check >> t) {
+        int idx = indexOf(whitelist, t);
+        if (idx == -1)
+            cout << t << endl;
+    }
+}

ch1/1_BinarySearch/tinyT.txt

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+23
+50
+10
+99
+18
+23
+98
+84
+11
+10
+48
+77
+13
+54
+98
+77
+77
+68

ch1/1_BinarySearch/tinyW.txt

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+84
+48
+68
+10
+18
+98
+12
+23
+54
+57
+33
+16
+77
+11
+29

ch1/2_RandomSeq/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.8)
+project(2_RandomSeq)
+
+set(CMAKE_CXX_STANDARD 14)
+
+set(SOURCE_FILES main.cpp)
+add_executable(2_RandomSeq ${SOURCE_FILES})

ch1/2_RandomSeq/main.cpp

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+#include <iostream>
+#include <vector>
+#include <iomanip>
+#include <algorithm>
+
+using namespace std;
+
+const int seed = 100;
+
+/**
+ * Reads in two command-line arguments lo and hi and prints n uniformly
+ * random real numbers in [lo, hi) to standard output.
+ *
+ * @param args the command-line arguments
+ */
+int main() {
+    int n = 10;
+    double lo = 0.0, hi = 1.0;
+    // uniform[0.0, 1.0)
+    default_random_engine e(seed);
+    uniform_real_distribution<double> dis(0.0, 1.0);
+    cout << fixed;
+    for (int i = 0; i < n; ++i)
+        cout << setprecision(4) << dis(e) << "  ";
+    cout << endl;
+    // uniform[lo, high)
+    lo = 2.5, hi = 3.0;
+    uniform_real_distribution<double> dis2(lo, hi);
+    for (int i = 0; i < n; ++i)
+        cout << setprecision(4) << dis2(e) << "  ";
+    cout << endl;
+}

ch1/3_Average/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.8)
+project(3_Average)
+
+set(CMAKE_CXX_STANDARD 14)
+
+set(SOURCE_FILES main.cpp)
+add_executable(3_Average ${SOURCE_FILES})

ch1/3_Average/main.cpp

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+#include <iostream>
+#include <vector>
+#include <iomanip>
+#include <algorithm>
+
+using namespace std;
+
+const int seed = 100;
+
+/**
+* Reads in a sequence of real numbers from standard input and prints
+* out their average to standard output.
+*
+* @param args the command-line arguments
+*/
+int main() {
+    int count = 0;
+    double sum = 0.0;
+    vector<double> arr{10.0, 5.0, 6.0, 3.0, 7.0, 32.0};
+    for (auto a: arr) {
+        sum += a;
+        count++;
+    }
+    double avg = sum / count;
+    cout << "Average is " << avg << endl;
+}

ch1/4_Cat/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.8)
+project(4_Cat)
+
+set(CMAKE_CXX_STANDARD 14)
+
+set(SOURCE_FILES main.cpp)
+add_executable(4_Cat ${SOURCE_FILES})

ch1/4_Cat/in1.txt

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+This is

ch1/4_Cat/in2.txt

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+a tiny
+test.

ch1/4_Cat/main.cpp

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+#include <iostream>
+#include <vector>
+#include <fstream>
+#include <algorithm>
+
+using namespace std;
+
+const int seed = 100;
+
+/**
+* Reads in a sequence of text files specified as the first command-line
+* arguments, concatenates them, and writes the results to the file
+* specified as the last command-line argument.
+*
+* @param args the command-line arguments
+*/
+int main() {
+    // TODO: change to relative path
+    ofstream out("/home/ace/AceDev/C++/algorithm/ch1/4_Cat/out.txt");
+    vector<string> files{"/home/ace/AceDev/C++/algorithm/ch1/4_Cat/in1.txt",
+                         "/home/ace/AceDev/C++/algorithm/ch1/4_Cat/in2.txt"};
+    string tmp;
+    for (int i = 0; i < files.size(); ++i) {
+        ifstream in(files[i]);
+        while (getline(in, tmp))
+            out << tmp << endl;
+        in.close();
+    }
+    out.close();
+}

ch1/4_Cat/out.txt

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+This is
+a tiny
+test.

ch1/5_Knuth/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.8)
+project(5_Knuth)
+
+set(CMAKE_CXX_STANDARD 14)
+
+set(SOURCE_FILES main.cpp)
+add_executable(5_Knuth ${SOURCE_FILES})

ch1/5_Knuth/cards.txt

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+2C 3C 4C 5C 6C 7C 8C 9C 10C JC QC KC AC
+2D 3D 4D 5D 6D 7D 8D 9D 10D JD QD KD AD
+2H 3H 4H 5H 6H 7H 8H 9H 10H JH QH KH AH
+2S 3S 4S 5S 6S 7S 8S 9S 10S JS QS KS AS

ch1/5_Knuth/cardsUnicode.txt

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+2♣ 3♣ 4♣ 5♣ 6♣ 7♣ 8♣ 9♣ 10♣ J♣ Q♣ K♣ A♣ 
+2♦ 3♦ 4♦ 5♦ 6♦ 7♦ 8♦ 9♦ 10♦ J♦ Q♦ K♦ A♦ 
+2♥ 3♥ 4♥ 5♥ 6♥ 7♥ 8♥ 9♥ 10♥ J♥ Q♥ K♥ A♥ 
+2♠ 3♠ 4♠ 5♠ 6♠ 7♠ 8♠ 9♠ 10♠ J♠ Q♠ K♠ A♠ 

ch1/5_Knuth/main.cpp

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+#include <iostream>
+#include <vector>
+#include <fstream>
+#include <iomanip>
+#include <algorithm>
+
+using namespace std;
+
+std::random_device rd;
+std::mt19937 gen(rd());
+
+/**
+* Rearranges an array of objects in uniformly random order
+* (under the assumption that {@code Math.random()} generates independent
+* and uniformly distributed numbers between 0 and 1).
+* @param a the array to be shuffled
+*/
+template<typename T>
+void shuffle_(vector<T> &a) {
+    int n = a.size();
+    for (int i = 0; i < n; i++) {
+        // choose index uniformly in [0, i]
+        uniform_int_distribution<> dis(0, i);
+        int r = dis(gen);
+        swap(a[r], a[i]);
+    }
+}
+
+template<typename T>
+void shuffleAlternate_(vector<T> &a) {
+    int n = a.size();
+    for (int i = 0; i < n; i++) {
+        // choose index uniformly in [i, n-1]
+        uniform_int_distribution<> dis(0, n - i);
+        int r = i + dis(gen);
+        swap(a[r], a[i]);
+    }
+}
+
+/**
+* Reads in a sequence of text files specified as the first command-line
+* arguments, concatenates them, and writes the results to the file
+* specified as the last command-line argument.
+*
+* @param args the command-line arguments
+*/
+int main() {
+    // TODO: change to relative path
+    ifstream file("/home/ace/AceDev/C++/algorithm/ch1/5_Knuth/cards.txt");
+    string tmp;
+    vector<string> a;
+    while (file >> tmp) {
+        a.push_back(tmp);
+    }
+    shuffle_(a);
+    for (int i = 0; i < a.size(); ++i) {
+        cout << setw(6)<<left<<a[i];
+        if ((i + 1) % 13 == 0)
+            cout << endl;
+    }
+}