diff --git a/README.md b/README.md
index 0551ede..1118fac 100644
--- a/README.md
+++ b/README.md
@@ -143,7 +143,7 @@ _WDP\* MIM UW_
   - [zad_3](./src/cw6/zad3/zad3_sadzawka.cpp): autor: @pixelkubek (C++):white_check_mark:
   - [zad3_ms](./src/cw6/zad3/zad3_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
 - [zad. 4.]
-  - [zad_4](./src/cw6/zad4/zad4.cpp): autor: @pixelkubek (C++) :white_check_mark:
+  - [zad_4](./src/cw6/zad4/zad4.cpp): autor: @pixelkubek (C++) :x:
   - [zad_4](./src/cw6/zad4/zad4_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
 - [zad. 5.]
   - [katastrofy](./src/cw6/zad5/katastrofy.cpp) (C++) :white_check_mark::microscope:
@@ -176,15 +176,21 @@ _WDP\* MIM UW_
   - [bars_linear](./src/cw7/zad1/bars_linear.cpp) (C++)
   - [median_of_medians](./src/cw7/zad1/median_of_medians.cpp) (C++)
   - [zad1_ms](./src/cw7/zad1/zad1_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
+  - [zad1_jc](./src/cw7/zad1/zad1jc.cpp): autor: @pixelkubek (C++)
 - [zad. 2.]
   - [contains_triangle](./src/cw7/zad2/contains_triangle.cpp) (C++)
   - [zad2_ms](./src/cw7/zad2/zad2_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
+  - [zad2_jc](./src/cw7/zad2/zad2jc.cpp): autor: @pixelkubek (C++)
+- [zad. 3.]
+  - [zad3_jc](./src/cw7/zad3/zad3jc.cpp): autor: @pixelkubek (C++)
 - [zad. 4.]
   - [max_combined_diff](./src/cw7/zad4/max_combined_diff.cpp) (C++)
   - [zad4_ms](./src/cw7/zad4/zad4_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
+  - [zad4_jc](./src/cw7/zad4/zad4jc.cpp): autor: @pixelkubek (C++)
 - [zad. 5.]
   - [beakers](./src/cw7/zad5/beakers.cpp) (C++)
   - [zad5_ms](./src/cw7/zad5/zad5_ms.cpp): autor: @MrD4rkne (C++) :white_check_mark:
+  - [zad5_jc](./src/cw7/zad5/zad5jc.cpp): autor: @pixelkubek (C++)
 - [zad. 6.]
   - [rejs](./src/cw7/zad6/rejs.cpp) (C++)
 - [zad. 6.]
@@ -222,7 +228,7 @@ _WDP\* MIM UW_
 - [zad. 14.]
   - [zad14_jc](./src/cw8/zad14/zad14jc.cpp): autor: @pixelkubek (C++) :white_check_mark:
 - [zad. 15.]
-  - [zad15_jc](./src/cw8/zad15/zad15jc.cpp): autor: @pixelkubek (C++) :white_check_mark:
+  - [zad15_jc](./src/cw8/zad15/zad15jc.cpp): autor: @pixelkubek (C++) :x:
 - [zad. 16.]
   - [zad16_jc](./src/cw8/zad16/zad16jc.cpp): autor: @pixelkubek (C++) :white_check_mark:
 - [zad. 17.]
@@ -260,6 +266,7 @@ _wkrótce_
 
 - [zad. 1.]
 - [zad. 2.]
+  - [zad2_jc](./src/kol2_22/zad2jc.cpp): autor: @pixelkubek (C++)
 
 ### [Kolokwium III 2022/2023](./pdf/2022_III_Kolokwium.pdf)
 
diff --git a/src/cw7/zad1/zad1jc.cpp b/src/cw7/zad1/zad1jc.cpp
new file mode 100644
index 0000000..3d068ee
--- /dev/null
+++ b/src/cw7/zad1/zad1jc.cpp
@@ -0,0 +1,27 @@
+#include<stdio.h>
+#include<vector>
+#include<algorithm>
+
+int słupki(const std::vector<int> s){
+    std::vector<int> kopia;
+    for(size_t i = 0; i < s.size(); i++){
+        kopia.push_back(s[i]);
+    }
+    std::sort(kopia.begin(), kopia.end());
+
+    int mediana = kopia[kopia.size() / 2];
+
+    int wynik = 0;
+
+    for(size_t i = 0; i < kopia.size(); i++){
+        wynik += abs(kopia[i] - mediana);
+    }
+
+    return wynik;
+}
+
+
+int main(){
+    printf("%i\n", słupki({6, 4, 3, 4, 5, 2, 3}));
+    return 0;
+}
\ No newline at end of file
diff --git a/src/cw7/zad2/zad2jc.cpp b/src/cw7/zad2/zad2jc.cpp
new file mode 100644
index 0000000..e5ae6d2
--- /dev/null
+++ b/src/cw7/zad2/zad2jc.cpp
@@ -0,0 +1,19 @@
+#include<stdio.h>
+#include<vector>
+#include<algorithm>
+
+bool trojkat(const std::vector<int> v){
+    std::vector<int> kopia(v);
+    std::sort(kopia.begin(), kopia.end());
+
+    for(size_t i = 2; i < kopia.size(); i++){
+        if(kopia[i] <= kopia[i - 1] + kopia[i - 2])
+            return true;
+    }
+
+    return false;
+}
+
+int main(){
+    printf("%i\n", trojkat({1, 5, 2, 4, 2, 4, 2}));
+}
\ No newline at end of file
diff --git a/src/cw7/zad3/zad3jc.cpp b/src/cw7/zad3/zad3jc.cpp
new file mode 100644
index 0000000..5587db0
--- /dev/null
+++ b/src/cw7/zad3/zad3jc.cpp
@@ -0,0 +1,56 @@
+#include<stdio.h>
+#include<vector>
+#include<algorithm>
+#include<queue>
+#include<stdlib.h>
+
+int zaokrDod(int a, int b){
+    if(2 * (a % b) >= b)
+        return a / b + 1;
+    return a / b;
+}
+
+int zaokrDzielenie(int a, int b){
+    return a * b > 0 ? zaokrDod(a, b) : -zaokrDod(abs(a), abs(b));
+}
+
+int przedzial(const std::vector<int> x, int r){
+    std::vector<int> kopia(x);
+    std::sort(kopia.begin(), kopia.end());
+    std::queue<int> q;
+
+    int suma = 0, elementy = 0, maxElementy = 0, wynik = 0;
+    int c;
+    bool wszystkieNaleza;
+
+    for(size_t i = 0; i < kopia.size(); i++){
+        q.push(kopia[i]);
+        suma += kopia[i];
+        ++elementy;
+
+        do
+        {
+            wszystkieNaleza = true;
+            c = zaokrDzielenie(suma, elementy); //c jest srednia z elementow
+            if(abs(q.front() - c) > r){
+                suma -= q.front();
+                --elementy;
+                q.pop();
+                wszystkieNaleza = false;
+            }
+        } while (!wszystkieNaleza);
+        //dla konktertnego i bede usuwal mniejsze elementy az kopia[i] sie zalicza
+        
+        if(elementy > maxElementy){
+            maxElementy = elementy;
+            wynik = c;
+        }
+    }
+
+    return wynik;
+}
+
+int main(){
+    printf("%i\n", przedzial({2, -2, 5, -1, 11, 8, 4, 5, 8, 7}, 2));
+    return 0;
+}
\ No newline at end of file
diff --git a/src/cw7/zad4/zad4jc.cpp b/src/cw7/zad4/zad4jc.cpp
new file mode 100644
index 0000000..db9884b
--- /dev/null
+++ b/src/cw7/zad4/zad4jc.cpp
@@ -0,0 +1,35 @@
+#include<stdio.h>
+#include<vector>
+#include<algorithm>
+
+std::vector<float> przekładaniec(const std::vector<float> x){
+    std::vector<float> v(x);
+    std::sort(v.begin(), v.end());
+    std::vector<float> wynik;
+
+    size_t odwiedzone = 1;
+    size_t i = 0, j = v.size() - 1;
+    wynik.push_back(v[(v.size() - 1) / 2]);
+    
+    while (odwiedzone < v.size() - 1)
+    {
+        wynik.push_back(v[j--]);
+        wynik.push_back(v[i++]);
+
+        odwiedzone += 2;
+    }
+
+    if(odwiedzone < v.size())
+        wynik.push_back(v[(v.size() - 1) / 2 + 1]);
+
+    return wynik;
+}
+
+int main(){
+    std::vector<float> wynik = przekładaniec({1, 2, 3, 4, 6});
+    for(auto val : wynik)
+        printf("%lf ", val);
+
+    printf("\n");
+    return 0;
+}
\ No newline at end of file
diff --git a/src/cw7/zad5/zad5jc.cpp b/src/cw7/zad5/zad5jc.cpp
new file mode 100644
index 0000000..eab3e97
--- /dev/null
+++ b/src/cw7/zad5/zad5jc.cpp
@@ -0,0 +1,40 @@
+#include<vector>
+#include<queue>
+#include<stdio.h>
+
+void przelej(std::queue<float> &v, std::queue<float> &q){
+    float zlane = 0;
+    for(int i = 0; i < 2; i++){
+        if(q.empty() || v.front() < q.front()){
+            zlane += v.front();
+            v.pop();
+        } else {
+            zlane += q.front();
+            q.pop();
+        }
+    }
+
+    q.push(zlane);
+}
+
+float zlewki(const std::vector<float> x, int k){
+    std::queue<float> v, q;
+    for(float val : x) v.push(val);
+
+    for(int i = 0; i < k; ++i){
+        przelej(v, q);
+    }
+
+    if(!v.empty() && !q.empty())
+        return std::min(v.front(), q.front());
+    else if(v.empty())
+        return q.front();
+    else
+        return v.front();
+
+}
+
+int main(){
+    printf("%lf\n", zlewki({1, 2, 3, 4, 5}, 3));
+    return 0;
+}
\ No newline at end of file
diff --git a/src/kol2_22/zad2jc.cpp b/src/kol2_22/zad2jc.cpp
new file mode 100644
index 0000000..a2862ed
--- /dev/null
+++ b/src/kol2_22/zad2jc.cpp
@@ -0,0 +1,45 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+typedef struct node *bin_tree;
+struct node {
+    int val;
+    bin_tree left, right;
+};
+
+bin_tree newNode(int val){
+    bin_tree nowy = (node*)malloc(sizeof(node));
+    nowy->val = val;
+    nowy->left = nowy->right = NULL;
+    return nowy;
+}
+
+void del_subtree(bin_tree t){
+    if(t == NULL) return;
+    del_subtree(t->left);
+    del_subtree(t->right);
+    free(t);
+}
+
+void bestify_subtree(bin_tree t, int maxx, int minn, bin_tree *pToME){
+    if(!t) return;
+    if(t->val >= maxx || t->val <= minn){
+        del_subtree(t);
+        *pToME = NULL;
+        return;
+    }
+
+    bestify_subtree(t->left, t->val, minn, &(t->left));
+    bestify_subtree(t->right, maxx, t->val, &(t->right));
+}
+
+
+int main(){
+    bin_tree t = newNode(10);
+    t->left = newNode(5);
+    t->left->right = newNode(15);
+    t->right = newNode(14);
+
+    bestify_subtree(t, __INT16_MAX__, -__INT_MAX__, &t);
+    return 0;
+}
\ No newline at end of file