diff --git a/du3/program.c b/du3/program.c
index e69de29..7b68ec5 100644
--- a/du3/program.c
+++ b/du3/program.c
@@ -0,0 +1,118 @@
+#include<stdio.h>
+#include<assert.h>
+#include<string.h>
+#include<stdlib.h>
+
+#define STACK_SIZE 10
+
+struct stack
+{
+   float values[STACK_SIZE];
+   int size;
+};
+
+void push_stack(struct stack* mystack, float value)
+{
+    assert(mystack->size<STACK_SIZE);
+    mystack->values[mystack->size]=value;
+    mystack->size+=1;
+}
+
+int switch_operators(const char input[])
+{
+    switch (input[0])
+    {
+    case '+':
+        return 0;
+        break;
+    case '-':
+        return 0;
+        break;
+    case '*':
+        return 0;
+        break;
+    case '/':
+        return 0;
+        break;
+    default:
+        return 1;
+        break;
+    }   
+}
+
+float pop_stack(struct stack* mystack,const char input[])
+{
+    assert(mystack->size>1);
+    float val1=mystack->values[mystack->size-2];
+    float val2=mystack->values[mystack->size-1];
+    switch (input[0])
+    {
+    case '+':
+        mystack->size-=2;
+        return val1+val2;
+        break;
+    case '-':
+        mystack->size-=2;
+        return val1-val2;
+        break;
+    case '*':
+        mystack->size-=2;
+        return val1*val2;
+        break;
+    case '/':
+        mystack->size-=2;
+        return val1/val2;
+        break;
+    default:
+        break;
+    }
+}
+
+int count_stack(struct stack* stack)
+{
+
+}
+
+void print_stack(struct stack* mystack)
+{
+    for(int i=0;i<mystack->size;i++)
+    {
+        printf("%f",mystack->values[i]);
+        if (i<mystack->size-1)
+        {
+            printf(" ");
+        }
+    }
+    printf("\n");
+}
+
+
+int main()
+{
+        struct stack mystack;
+        memset(&mystack,0,sizeof(struct stack));
+        char input[1000];
+        while (fgets(input,sizeof(input),stdin)!=NULL)
+        {
+            int flag=switch_operators(input);
+            input[strcspn(input,"\n")]=0;
+            if (strlen(input)==0) 
+            {
+                continue;
+            }
+            if (flag==0)
+            {
+                float op_num=pop_stack(&mystack,input);
+                push_stack(&mystack,op_num);
+            }
+            else
+            {
+                char* ptr;
+                float num=strtof(input,&ptr);
+                push_stack(&mystack,num);
+            }
+            print_stack(&mystack);
+        }        
+        return 0;
+}
+