diff --git a/cv3/program.c b/cv3/program.c
new file mode 100644
index 0000000..ce0b796
--- /dev/null
+++ b/cv3/program.c
@@ -0,0 +1,94 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+#define STACK_SIZE 50
+
+struct stack
+{
+   float values[STACK_SIZE];
+   int size;
+};
+
+void add(struct stack* stack, float num)
+{
+    assert(stack->size < STACK_SIZE);
+    stack->values[stack->size] = num;
+    stack->size++;
+}
+
+float getnpop(struct stack* stack)
+{
+    assert(stack->size > 0);
+    float value = stack->values[stack->size-1];
+    stack->size -= 1;
+    return value;
+}
+
+
+float calculate(struct stack* stack, char operator)
+{
+    float num1 = getnpop(stack);
+    float num2 = getnpop(stack);
+    float res = 0;
+
+    switch(operator)
+    {
+        case '+':
+            res = num1+num2;
+        break;
+        case '-':
+            res = num1-num2;
+        break;
+        case '*':
+            res = num1*num2;
+        break;
+        case '/':
+            res = num1/num2;
+        break;
+    }
+    add(stack, res);
+    return res;
+}
+
+int main(int argc, char const *argv[])
+{
+    char buf[50];
+    struct stack calc_stack;
+    float num  = 0;
+    int s = 0;
+    memset(buf, 0, 50);
+    memset(&calc_stack,0,sizeof(struct stack));
+
+    while (fgets(buf, 50, stdin) != NULL)
+    {
+        if(buf[0] == '\n')
+        {
+            break;
+        }
+
+        buf[strcspn(buf, "\n")] = '\0';
+        num = atof(buf);
+        if(num != 0)
+        {
+            add(&calc_stack, num);
+        }
+        else
+        {
+            calculate(&calc_stack, buf[0]);
+        }
+        for (int i = 0; i < calc_stack.size; i++)
+        {
+            printf("%f ", calc_stack.values[i]);
+        }
+        printf("\n");
+        // if (scanf("%f", &num) != 1)
+        // {
+        //     break;
+        // }
+
+        //getchar();
+    }
+    return 0;
+}