diff --git a/1sem/programming basics/13/100.cpp b/1sem/programming basics/13/100.cpp
index fe6fee2..3294d59 100644
--- a/1sem/programming basics/13/100.cpp	
+++ b/1sem/programming basics/13/100.cpp	
@@ -1,50 +1,75 @@
-// pb_13_100.cpp
+// pb_15_100.cpp
 // Горбацевич Андрей
 #include <iostream>
+#include <fstream>
 
 using namespace std;
 
-void print_mtx(int **mtx, int w, int h, ostream &ost);
-int **generate_mtx(int n);
+void text2bin(istream &ist, ostream &ost);
 
-int main()
-{
-    ofstream fout("out.txt", ios::trunc);
-    if (!fout.is_open())
+void my_task(istream &ist);
+
+int main() {
+    ifstream ifs("in.txt");
+    ofstream ofs("out.bin", ios::trunc|ios::binary);
+    if (!ifs.is_open())
     {
         cerr << "Unable to open file" << endl;
         return 1;
     }
-	
-	int n;
-	cout << "n >>>";
-	cin >> n;
-	int **mtx = generate_mtx(n);
-	print_mtx(mtx, n, n, fout);
+
+    text2bin(ifs, ofs);
+    my_task(ifs);
+
+    return 0;
 }
 
-void print_mtx(int **mtx, int w, int h, ostream &ost) {
-	for (int i = 0; i < w; i++) {
-		for (int j = 0; j < h; j++) {
-			ost << *(*(mtx + i) + j) << " ";
-		}
-		ost << endl;
-	}
-	ost << endl;
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << N << ' ' << M;
+    for (int i = 0; i < N; i++) {
+        ost << endl;
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << cv << ' ';
+        }
+    }
 }
 
-int **generate_mtx(int n) {
-	int **mtx = new int*[n];
-	for (int i = 0; i < n; i++) {
-		int *row = new int[n]();
-		int pos = n;
-		for (int j = -n+i; j < 0; j++) {
-			*(row + pos--) = abs(j);
-		}
-		for (int j = 0; pos >= 0; j++) {
-			*(row + pos--) = abs(j);
-		}
-		*(mtx + i) = row;
-	}
-	return mtx;
-}
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N, M;
+    ist >> N >> M;
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            *(row + j) = cv;
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        for (int j = 1; j < M; j++) {
+            if (mtx[i][j-1] < mtx[i][j]) {
+                bool flag = false;
+                for (int v = 0; v < M; v++) {
+                    if (mtx[i][v] == k) {
+                        flag = true;
+                        break;
+                    }
+                }
+                if (flag) {
+                    cout << "Line " << i + 1 << " contains k(k==" << k << ")\n";
+                }
+                break;
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/100.cpp b/2sem/programming basics/15/100.cpp
new file mode 100644
index 0000000..c68200b
--- /dev/null
+++ b/2sem/programming basics/15/100.cpp	
@@ -0,0 +1,79 @@
+// pb_15_100_v5.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+            M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        for (int j = 1; j < M; j++) {
+            if (mtx[i][j-1] < mtx[i][j]) {
+                bool flag = false;
+                for (int v = 0; v < M; v++) {
+                    if (mtx[i][v] == k) {
+                        flag = true;
+                        break;
+                    }
+                }
+                if (flag) {
+                    cout << "Line " << i + 1 << " contains k(k==" << k << ")\n";
+                    break;
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/additional/100_1.cpp b/2sem/programming basics/15/additional/100_1.cpp
new file mode 100644
index 0000000..63554a8
--- /dev/null
+++ b/2sem/programming basics/15/additional/100_1.cpp	
@@ -0,0 +1,90 @@
+// pb_15_100_v1.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+        M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        bool flag = true;
+        int *row = mtx[i];
+        for (int j = 1; j < M; j++) {
+            if (row[j-1] < row[j]) {
+                flag = false;
+                break;
+            }
+        }
+        if (flag) {
+            int l = 0,
+                r = M-1;
+            int m;
+            while (l<=r) {
+                m = (l+r) / 2;
+                if (k < row[m]) {
+                    l = m+1;
+                }
+                else if (k > row[m]) {
+                    r = m-1;
+                }
+                else {
+                    cout << "Line " << i + 1 << " is descending and contains k(k==" << k << ")\n";
+                    break;
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/additional/100_2.cpp b/2sem/programming basics/15/additional/100_2.cpp
new file mode 100644
index 0000000..22a4b29
--- /dev/null
+++ b/2sem/programming basics/15/additional/100_2.cpp	
@@ -0,0 +1,83 @@
+// pb_15_100_v2.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+        M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        bool flag = true;
+        int *row = mtx[i];
+        int *ic = new int[M]();
+        for (int j = 0; j < M; j++) {
+            for (int k = j+1; k < M; k++) {
+                if (row[j] == row[k]) {
+                    ic[j] += 1;
+                }
+            }
+        }
+        int mx = ic[0],
+            mxp = 0;
+        for (int j = 1; j < M; j++) {
+            if (mx < ic[j]) {
+                mx = ic[j];
+                mxp = j;
+            }
+        }
+        cout << "Most common on line " << i+1 << ": " << row[mxp] << endl;
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/additional/100_3.cpp b/2sem/programming basics/15/additional/100_3.cpp
new file mode 100644
index 0000000..386f7cb
--- /dev/null
+++ b/2sem/programming basics/15/additional/100_3.cpp	
@@ -0,0 +1,90 @@
+// pb_15_100_v3.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+        M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        bool flag = true;
+        int *row = mtx[i];
+        for (int j = 1; j < M; j++) {
+            if (row[j-1] > row[j]) {
+                flag = false;
+                break;
+            }
+        }
+        if (flag) {
+            int l = 0,
+                r = M-1;
+            int m;
+            while (l<=r) {
+                m = (l+r) / 2;
+                if (k > row[m]) {
+                    l = m+1;
+                }
+                else if (k < row[m]) {
+                    r = m-1;
+                }
+                else {
+                    cout << "Line " << i + 1 << " is ascending and contains k(k==" << k << ")\n";
+                    break;
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/additional/100_4.cpp b/2sem/programming basics/15/additional/100_4.cpp
new file mode 100644
index 0000000..6bf35f0
--- /dev/null
+++ b/2sem/programming basics/15/additional/100_4.cpp	
@@ -0,0 +1,82 @@
+// pb_15_100_v4.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+        M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        int *row = mtx[i];
+        bool flag = true;
+        for (int sk = 1; sk <= k; sk++) {
+            bool cc = false;
+            for (int j = 0; j < M; j++) {
+                if (row[j] == sk) {
+                    cc = true;
+                    break;
+                }
+            }
+            if (!cc) {
+                flag = false;
+                break;
+            }
+        }
+        if (flag) {
+            cout << "Line " << i+1 << " contains every number in 1..." << k << endl;
+        }
+    }
+}
\ No newline at end of file
diff --git a/2sem/programming basics/15/additional/100_5.cpp b/2sem/programming basics/15/additional/100_5.cpp
new file mode 100644
index 0000000..9606c3b
--- /dev/null
+++ b/2sem/programming basics/15/additional/100_5.cpp	
@@ -0,0 +1,79 @@
+// pb_15_100_v5.cpp
+// Горбацевич Андрей
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+void text2bin(istream &ist, ostream &ost);
+
+void my_task(istream &ist);
+
+int main() {
+    string path_in = "in.txt"; // путь до входного файла
+    string path_out = "out.bin"; // путь до выходного файла
+
+    ifstream ifs(path_in);
+    ofstream ofs(path_out, ios::binary);
+    if (!ifs.is_open())
+    {
+        cerr << "Unable to open file" << endl;
+        return 1;
+    }
+
+    text2bin(ifs, ofs);
+    ifs.close();
+    ofs.close();
+
+    ifstream binfs(path_out, ios::binary);
+    my_task(binfs);
+
+    return 0;
+}
+
+void text2bin(istream &ist, ostream &ost) {
+    int N, M;
+    ist >> N >> M;
+    ost << char(N) << char(M);
+    for (int i = 0; i < N; i++) {
+        for (int j = 0; j < M; j++) {
+            int cv;
+            ist >> cv;
+            ost << char(cv);
+        }
+    }
+}
+
+void my_task(istream &ist) {
+    ist.seekg(0, ios::beg);
+    int k;
+    cout << "k >>>";
+    cin >> k;
+    int N = int(ist.get()),
+        M = int(ist.get());
+    int **mtx = new int*[N];
+    for (int i = 0; i < N; i++) {
+        int *row = new int[M]();
+        for (int j = 0; j < M; j++) {
+            *(row + j) = int(ist.get());
+        }
+        *(mtx + i) = row;
+    }
+    for (int i = 0; i < N; i++) {
+        for (int j = 1; j < M; j++) {
+            if (mtx[i][j-1] < mtx[i][j]) {
+                bool flag = false;
+                for (int v = 0; v < M; v++) {
+                    if (mtx[i][v] == k) {
+                        flag = true;
+                        break;
+                    }
+                }
+                if (flag) {
+                    cout << "Line " << i + 1 << " contains k(k==" << k << ")\n";
+                    break;
+                }
+            }
+        }
+    }
+}
\ No newline at end of file