add sorting tasks

src/cw7/zad1/bars.cpp

@@ -0,0 +1,17 @@
+/*
+T(n) = O(nlogn) - przez sortowanie
+M(n) = O(1)
+*/
+
+#include <algorithm>
+#include <vector>
+
+int bars(std::vector<int> v) {
+    int ans = 0;
+    std::sort(v.begin(), v.end());
+    int median = v[v.size()/2];
+    for (auto el : v)
+        ans += abs(el - median);
+
+    return ans;
+}

src/cw7/zad1/bars_linear.cpp

@@ -0,0 +1,22 @@
+/*
+T(n) = O(n)
+M(n) = O(1)
+*/
+
+//https://cs.stackexchange.com/questions/1914/find-median-of-unsorted-array-in-on-time
+
+#include <algorithm>
+#include <vector>
+
+int median_of_medians() {
+    return 0;
+}
+
+int bars_linear(std::vector<int> v) {
+    int ans = 0;
+    int median = median_of_medians();
+    for (auto el : v)
+        ans += abs(el - median);
+
+    return ans;
+}

src/cw7/zad1/median_of_medians.cpp

@@ -0,0 +1,107 @@
+//https://stackoverflow.com/questions/9683343/median-of-median-implementation
+
+#include <iostream>
+#include <vector>
+#include <algorithm>
+using namespace std;
+
+int findMedian(vector<int> vec){
+//    Find median of a vector
+    int median;
+    size_t size = vec.size();
+    median = vec[(size/2)];
+    return median;
+}
+
+int findMedianOfMedians(vector<vector<int> > values){
+    vector<int> medians;
+
+    for (int i = 0; i < values.size(); i++) {
+        int m = findMedian(values[i]);
+        medians.push_back(m);
+    }
+
+    return findMedian(medians);
+}
+
+void selectionByMedianOfMedians(const vector<int> values, int k){
+//    Divide the list into n/5 lists of 5 elements each
+    vector<vector<int> > vec2D;
+
+    int count = 0;
+    while (count != values.size()) {
+        int countRow = 0;
+        vector<int> row;
+
+        while ((countRow < 5) && (count < values.size())) {
+            row.push_back(values[count]);
+            count++;
+            countRow++;
+        }
+        vec2D.push_back(row);
+    }
+
+    cout<<endl<<endl<<"Printing 2D vector : "<<endl;
+    for (int i = 0; i < vec2D.size(); i++) {
+        for (int j = 0; j < vec2D[i].size(); j++) {
+            cout<<vec2D[i][j]<<" ";
+        }
+        cout<<endl;
+    }
+    cout<<endl;
+
+//    Calculating a new pivot for making splits
+    int m = findMedianOfMedians(vec2D);
+    cout<<"Median of medians is : "<<m<<endl;
+
+//    Partition the list into unique elements larger than 'm' (call this sublist L1) and
+//    those smaller them 'm' (call this sublist L2)
+    vector<int> L1, L2;
+
+    for (int i = 0; i < vec2D.size(); i++) {
+        for (int j = 0; j < vec2D[i].size(); j++) {
+            if (vec2D[i][j] > m) {
+                L1.push_back(vec2D[i][j]);
+            }else if (vec2D[i][j] < m){
+                L2.push_back(vec2D[i][j]);
+            }
+        }
+    }
+
+//    Checking the splits as per the new pivot 'm'
+    cout<<endl<<"Printing L1 : "<<endl;
+    for (int i = 0; i < L1.size(); i++) {
+        cout<<L1[i]<<" ";
+    }
+
+    cout<<endl<<endl<<"Printing L2 : "<<endl;
+    for (int i = 0; i < L2.size(); i++) {
+        cout<<L2[i]<<" ";
+    }
+
+//    Recursive calls
+    if ((k - 1) == L1.size()) {
+        cout<<endl<<endl<<"Answer :"<<m;
+    }else if (k <= L1.size()) {
+        return selectionByMedianOfMedians(L1, k);
+    }else if (k > (L1.size() + 1)){
+        return selectionByMedianOfMedians(L2, k-((int)L1.size())-1);
+    }
+
+}
+
+int main()
+{
+    int values[] = {2, 3, 5, 4, 1, 12, 11, 13, 16, 7, 8, 6, 10, 9, 17, 15, 19, 20, 18, 23, 21, 22, 25, 24, 14};
+
+    vector<int> vec(values, values + 25);
+
+    cout<<"The given array is : "<<endl;
+    for (int i = 0; i < vec.size(); i++) {
+        cout<<vec[i]<<" ";
+    }
+
+    selectionByMedianOfMedians(vec, 8);
+
+    return 0;
+}

src/cw7/zad2/contains_triangle.cpp

@@ -0,0 +1,3 @@
+bool contains_triangle() {
+
+}

src/cw7/zad4/max_combined_diff.cpp

@@ -0,0 +1,5 @@
+//https://math.stackexchange.com/questions/3974110/sorting-an-array-to-get-the-maximum-combined-sum-of-the-differences-between-ever
+
+#include <vector>
+
+std::vector<float> max_combined_diff() {}