diff --git a/CMakeLists.txt b/CMakeLists.txt
index 409c998..b17af59 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,6 +15,12 @@ add_executable(skola calc.c
         main_rovnice.h
         kruh.h
         calc.h
-        znak.c)
+        znak.c
+        lepsiznak.c
+        lepsiznak.h
+        bomba.c
+        bomba.h
+        do_while_znak.c
+        do_while_znak.h)
 
 target_link_libraries(skola m)
diff --git a/bomba.c b/bomba.c
new file mode 100644
index 0000000..67d861c
--- /dev/null
+++ b/bomba.c
@@ -0,0 +1,23 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+#include "bomba.h"
+#include "stdio.h"
+#include "unistd.h"
+
+int dake_cislo(){
+    int a;
+
+    printf("Zadaj číslo:");
+    scanf("%d", &a);
+
+    do{
+        printf("%d\n", a);
+        usleep(1000000);
+        a--;
+
+    } while (a >= 0);
+    printf("\nAdlerka vybuchla (BOOOOOOOOOOM).\n");
+
+}
\ No newline at end of file
diff --git a/bomba.h b/bomba.h
new file mode 100644
index 0000000..aa24586
--- /dev/null
+++ b/bomba.h
@@ -0,0 +1,6 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+
+int dake_cislo();
\ No newline at end of file
diff --git a/calc.c b/calc.c
index 92c4a14..ef88f72 100644
--- a/calc.c
+++ b/calc.c
@@ -2,38 +2,43 @@
 #include "math.h"
 #include "calc.h"
 int calc(){
-    double a = 0;
-    double b = 0;
-    char operacia = 0;
-    double vysledok = 0;
-    printf("Zadaj prvé číslo:\n");
-    scanf("%lf", &a);
-    printf("Zadaj druhé číslo:\n");
-    scanf("%lf", &b);
-    printf("Zadaj operáciu(+ - * /):\n");
-    scanf(" %c", &operacia);
-    vysledok = a;
-    switch (operacia) {
-        case '+':
-            vysledok += b;
-            break;
+    char pokracovat = 'a';
+    while (pokracovat == 'a') {
+        double a = 0;
+        double b = 0;
+        char operacia = 0;
+        double vysledok = 0;
+        printf("Zadaj prvé číslo:\n");
+        scanf("%lf", &a);
+        printf("Zadaj druhé číslo:\n");
+        scanf("%lf", &b);
+        printf("Zadaj operáciu(+ - * /):\n");
+        scanf(" %c", &operacia);
+        vysledok = a;
+        switch (operacia) {
+            case '+':
+                vysledok += b;
+                break;
 
-        case '-':
-            vysledok -= b;
-            break;
+            case '-':
+                vysledok -= b;
+                break;
 
-        case '*':
-            vysledok *= b;
-            break;
+            case '*':
+                vysledok *= b;
+                break;
 
-        case '/':
-            vysledok /= b;
-            break;
+            case '/':
+                vysledok /= b;
+                break;
 
-        default:
-            printf("Nesprávna operácia.\n");
-            return 1;
+            default:
+                printf("Nesprávna operácia.\nPrajete si pokračovať(a/n)?\n");
+                scanf("%s", &pokracovat);
+        }
+        printf("Vysledok %f %c %f je: %f.\nPrajete si pokračovať(a/n)?\n", a, operacia, b, vysledok);
+        scanf("%s", &pokracovat);
     }
-    printf("Vysledok %f %c %f je: %f\nKalkulačka skončila úspešne.\n", a, operacia, b, vysledok);
     return 0;
+
 }
\ No newline at end of file
diff --git a/do_while_znak.c b/do_while_znak.c
new file mode 100644
index 0000000..603b42b
--- /dev/null
+++ b/do_while_znak.c
@@ -0,0 +1,21 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+#include "do_while_znak.h"
+#include "stdio.h"
+
+
+int do_while_znak(){
+    int c;
+    int pocet = 0;
+    const int koniec = 'k';
+
+    do {
+        c = getchar();
+        putchar(c);
+        pocet++;
+    } while (c != koniec);
+    printf("\nVydržal si %d znakov pred tým, ako si napísal %c (vrátane) .\n", pocet, koniec);
+    return 0;
+}
\ No newline at end of file
diff --git a/do_while_znak.h b/do_while_znak.h
new file mode 100644
index 0000000..6c82103
--- /dev/null
+++ b/do_while_znak.h
@@ -0,0 +1,5 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+int do_while_znak();
\ No newline at end of file
diff --git a/lepsiznak.c b/lepsiznak.c
new file mode 100644
index 0000000..dd2320e
--- /dev/null
+++ b/lepsiznak.c
@@ -0,0 +1,31 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+#include "lepsiznak.h"
+#include "stdio.h"
+
+void invertcase(int *c){
+    if (*c >= 'a' && *c <= 'z'){
+        *c -= 0x20;
+    }
+    else if (*c >= 'A' && *c <= 'Z'){
+        *c += 0x20;
+    }
+}
+
+int lepsiznak(){
+
+    int c;
+    int pocet = 0;
+    const int koniec = 'k';
+
+    while ( (c = getchar()) != koniec){
+        invertcase(&c);
+        putchar(c);
+        pocet++;
+    }
+    printf("\nVydržal si %d znakov pred tým, ako si napísal %c.\n", pocet, koniec);
+    return 0;
+
+}
diff --git a/lepsiznak.h b/lepsiznak.h
new file mode 100644
index 0000000..34e7804
--- /dev/null
+++ b/lepsiznak.h
@@ -0,0 +1,7 @@
+//
+// Created by bruno on 12/11/23.
+//
+
+int lepsiznak();
+
+void invertcase(int *c);
diff --git a/main.c b/main.c
index 5f850c6..ffac919 100644
--- a/main.c
+++ b/main.c
@@ -1,5 +1,5 @@
-#include "znak.h"
+#include "calc.h"
 
 int main(){
-    return znak();
+    return calc();
 }
\ No newline at end of file
diff --git a/znak.c b/znak.c
index 5115363..b4a7cf7 100644
--- a/znak.c
+++ b/znak.c
@@ -1,5 +1,7 @@
 #include "stdio.h"
+
 int znak(){
+
     char in;
     printf("Zadaj znak:");
     scanf("%c", &in);