From a5534f16ecaf4b93f1bcd775f1e1df64203b3b65 Mon Sep 17 00:00:00 2001
From: Santo Cariotti <santo@dcariotti.me>
Date: Fri, 11 Nov 2022 11:07:40 +0100
Subject: Add `ordinamento-lineare`

---
 .../data_structures/cc/ordinamento-lineare.cc      | 115 +++++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 Year_2/Algorithms/data_structures/cc/ordinamento-lineare.cc

diff --git a/Year_2/Algorithms/data_structures/cc/ordinamento-lineare.cc b/Year_2/Algorithms/data_structures/cc/ordinamento-lineare.cc
new file mode 100644
index 0000000..5af1b1d
--- /dev/null
+++ b/Year_2/Algorithms/data_structures/cc/ordinamento-lineare.cc
@@ -0,0 +1,115 @@
+#include <fstream>
+#include <iostream>
+#include <stdlib.h>
+#include <string>
+
+using namespace std;
+
+template <typename T>
+void
+counting_sort(T* A, size_t n, ofstream& fout, int incr, bool is_char = false)
+{
+    int i, j;
+    int max, min;
+    int* freq;
+    int* t;
+    int range;
+
+    for (i = 0; i < n; ++i) {
+        A[i] = A[i] * incr;
+    }
+
+    max = A[0], min = A[0];
+    t = new int[n];
+
+    for (i = 1; i < n; ++i) {
+        if (A[i] > max)
+            max = A[i];
+
+        if (A[i] < min)
+            min = A[i];
+    }
+
+    range = (max - min) + 1;
+
+    freq = new int[range];
+
+    for (i = 0; i < range; ++i) {
+        freq[i] = 0;
+    }
+
+    for (i = 0; i < n; ++i) {
+        freq[static_cast<int>(A[i] - min)] += 1;
+    }
+    for (i = 1; i < range; ++i) {
+        freq[i] = freq[i] + freq[i - 1];
+    }
+    fout << "0 ";
+    for (i = 0; i < range - 1; ++i) {
+        fout << freq[i] << ' ';
+    }
+
+    for (i = n - 1; i >= 0; --i) {
+        t[freq[static_cast<int>(A[i] - min)] - 1] = A[i];
+        freq[static_cast<int>(A[i] - min)]--;
+    }
+
+    for (i = 0; i < n; ++i) {
+        A[i] = t[i];
+        if (is_char) {
+            fout << (char)A[i] << ' ';
+        } else {
+            fout << A[i] / incr << ' ';
+        }
+    }
+    fout << endl;
+
+    delete[] freq;
+    delete[] t;
+}
+
+int
+main()
+{
+    ifstream fin("input.txt");
+    ofstream fout("output.txt");
+    string type;
+    int N;
+
+    for (int i = 0; i < 100; ++i) {
+        fin >> type;
+        fin >> N;
+
+        if (type == "double") {
+            double* a = new double[N];
+
+            for (int j = 0; j < N; ++j) {
+                fin >> a[j];
+            }
+
+            counting_sort(a, N, fout, 10);
+
+            delete[] a;
+        } else if (type == "char") {
+            char* a = new char[N];
+
+            for (int j = 0; j < N; ++j) {
+                fin >> a[j];
+            }
+
+            counting_sort(a, N, fout, 1, true);
+            delete[] a;
+        } else {
+            int* a = new int[N];
+
+            for (int j = 0; j < N; ++j) {
+                fin >> a[j];
+            }
+
+            counting_sort(a, N, fout, 1);
+            delete[] a;
+        }
+    }
+
+    return 0;
+}
-- 
cgit v1.2.3-18-g5258