diff --git a/du1/program.c b/du1/program.c
new file mode 100644
index 0000000..a0b39e7
--- /dev/null
+++ b/du1/program.c
@@ -0,0 +1,28 @@
+nclude <stdlib.h>
+#include <stdio.h>
+#include <ctype.h>
+
+int main()
+{   
+    char simb;
+    int riad=0;
+    while(1){
+    simb=getchar();
+    if(islower(simb)){
+        simb-=32;
+    }
+    else if (isupper(simb)){
+        simb+=32;
+    }
+    else if(simb==EOF){
+        break;    
+    }
+    putchar(simb);
+    if(simb=='\n'){
+    riad++;
+    }
+    }
+    printf("%d",riad);
+    return 0;
+}
+