diff --git a/a1/program.c b/a1/program.c
new file mode 100644
index 0000000..0b07f64
--- /dev/null
+++ b/a1/program.c
@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+int main() {
+    char line[100];
+    double num1, num2, result, expected_result;
+    char op;
+
+    while (fgets(line, sizeof(line), stdin) != NULL) {
+        num1 = num2 = result = 0;
+        op = '\0';
+
+        // Remove any spaces between symbols
+        for (int i = 0; line[i] != '\0'; i++) {
+            if (isspace(line[i])) {
+                for (int j = i; line[j] != '\0'; j++) {
+                    line[j] = line[j + 1];
+                }
+                i--; // Move back one step to recheck the current character
+            }
+        }
+
+        // Parse the line
+        sscanf(line, "%lf%c%lf=%lf", &num1, &op, &num2, &expected_result);
+
+        // Check if the input is valid
+        if (op != '+' && op != '-' && op != '*' && op != '/') {
+            printf("CHYBA\n");
+            continue;
+        }
+
+        // Check for division by zero
+        if (op == '/' && num2 == 0) {
+            printf("CHYBA\n");
+            continue;
+        }
+
+        // Perform the calculation
+        switch (op) {
+            case '+':
+                result = num1 + num2;
+                break;
+            case '-':
+                result = num1 - num2;
+                break;
+            case '*':
+                result = num1 * num2;
+                break;
+            case '/':
+                result = num1 / num2;
+                break;
+        }
+
+        // Check if the result is correct
+        if (result == expected_result) {
+            printf("OK\n");
+        } else {
+            printf("ZLE\n");
+        }
+    }
+
+    return 0;
+}