diff --git a/Topic-11/server.c b/Topic-11/server.c
index cdac6ce..7cc568b 100644
--- a/Topic-11/server.c
+++ b/Topic-11/server.c
@@ -19,7 +19,7 @@ void handle_arguments(int argc, char *argv[]) {
 
 struct TokenizedQuerry tokenize(const char *querry) {
     struct TokenizedQuerry tokenized_querry;
-    printf("QUERRY: %s\n", querry);
+    // printf("QUERRY: %s\n", querry);
     char left[50], *operand_ptr, right[50];
     char valid_operands[4] = {'+', '-', '/', '*'};
     for (int i = 0; i < sizeof(valid_operands); ++i) {
@@ -34,13 +34,29 @@ struct TokenizedQuerry tokenize(const char *querry) {
 
     strncpy(left, querry, left_length);
     strcpy(right, querry + left_length + 1);
-    printf("Tokenized: %s %c %s\n", left, *operand_ptr, right);
+    // printf("Tokenized: %s %c %s\n", left, *operand_ptr, right);
     tokenized_querry.left = strtol(left, NULL, 10);
     tokenized_querry.operand = *operand_ptr;
+    tokenized_querry.right = strtol(right, NULL, 10);
 
     return tokenized_querry;
 }
 
+int calculate_TokenizedQuerry(struct TokenizedQuerry expression) {
+    switch (expression.operand) {
+        case '+':
+            return expression.left + expression.right;
+        case '-':
+            return expression.left - expression.right;
+        case '*':
+            return expression.left * expression.right;
+        case '/':
+            return expression.left / expression.right;
+    }
+
+    return 0;
+}
+
 void run_server(int port) {
     int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
     if (sockfd < 0) {
@@ -61,16 +77,19 @@ void run_server(int port) {
         exit(EXIT_FAILURE);
     }
 
-    char buffer[100];
-    memset(&buffer, 0, sizeof(buffer));
+    size_t buffer_size = 100;
+    char buffer[buffer_size];
+    memset(&buffer, 0, buffer_size);
     socklen_t client_addr_len;
     struct TokenizedQuerry tokenized_querry;
 
     while (1) {
-        rv = recvfrom(sockfd, buffer, sizeof(buffer), 0, (struct sockaddr *)&client_addr, &client_addr_len);
+        rv = recvfrom(sockfd, buffer, buffer_size, 0, (struct sockaddr *)&client_addr, &client_addr_len);
         tokenized_querry = tokenize(buffer);
-        
-        //rv = sendto(sockfd, response, sizeof(response), 0, (const struct sockaddr *)&client_addr, sizeof(client_addr));
+        int result = calculate_TokenizedQuerry(tokenized_querry);
+        memset(&buffer, 0, buffer_size);
+        snprintf(buffer, buffer_size, "%d", result);
+        rv = sendto(sockfd, buffer, sizeof(buffer), 0, (const struct sockaddr *)&client_addr, sizeof(client_addr));
         memset(&buffer, 0, sizeof(buffer));
     }