diff --git a/algorithms/ciphers/vigenere_cipher.c b/algorithms/ciphers/vigenere_cipher.c
new file mode 100644
index 00000000..9ab03396
--- /dev/null
+++ b/algorithms/ciphers/vigenere_cipher.c
@@ -0,0 +1,138 @@
+/*
+=======================================================
+Algorithm: Vigenere Cipher
+=======================================================
+*/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+void encryption ();
+void decryption ();
+
+int main() {
+	
+	int choice;
+
+retry:
+	// Taking users choice
+	printf("Choose an option: \n");
+	printf("  1. Encryption\n  2. Decryption\n");
+	scanf("%d", &choice);
+	while (getchar() != '\n');
+
+	if (choice == 1) {
+		encryption();
+	} else if (choice == 2) {
+		decryption();
+	} else goto  retry;
+
+	return 0;
+}
+
+// envryption function
+void encryption () {
+	
+	char chain[100];
+	char key[100];
+	char text[100];
+	char alphabet[] = "abcdefghijklmnopqrstuvwxyz";
+	int poschain, poskey, postext;
+	int lenchain, lenkey;
+	int textIndex = 0;
+
+	// Taking Plaintext
+	system("cls || clear");
+	printf("Enter plaintext : ");
+	scanf("%[^\n]", chain);
+	while (getchar() != '\n');
+
+	// Taking key
+	printf("Enter encryption key : ");
+	scanf("%[^\n]", key);
+	while (getchar() != '\n');
+	system("cls || clear");
+
+	for (int i = 0; chain[i]; i++) {
+		chain[i] = tolower(chain[i]);
+	}
+	for (int i = 0; key[i]; i++) {
+		key[i] = tolower(key[i]);
+	}
+
+	lenchain = strlen(chain);
+	lenkey = strlen(key);
+	// Encryption
+	for (int i = 0; i < lenchain; i++) {
+		poskey = i % lenkey;
+
+		poschain = chain[i] - 'a';
+		poskey = key[poskey] - 'a';
+
+		//Text concatenation
+		postext = (poschain + poskey) % 26;
+		text[textIndex++] = alphabet[postext];
+	}
+	
+	// terminate the string with a '\0'
+	text[textIndex] = '\0';
+
+	// print result
+	system("cls || clear");
+	printf("-======[ Vigenere cipher ]============-\n\n");
+	printf("\t- Plaintext: %s\n", chain);
+	printf("\t- Key : %s\n", key);
+	printf("\t- Vigenere ciphertext : %s\n", text);
+	getchar ();
+}
+
+void decryption () {
+
+	char chain[100];
+	char key[100];
+	char text[100];
+	char alphabet[] = "abcdefghijklmnopqrstuvwxyz";
+	int poschain, poskey, postext;
+	int lenchain, lenkey, choice;
+	int textIndex = 0;
+
+	system("cls || clear");
+	printf("Enter ciphertext : ");
+	scanf("%[^\n]", chain);
+	while (getchar() != '\n');
+
+	printf("Enter encryption key : ");
+	scanf("%[^\n]", key);
+	while (getchar() != '\n');
+
+	// converting chain and key to lowercase to  facilitate string management 
+	for (int i = 0; chain[i]; i++) {
+		chain[i] = tolower(chain[i]);
+	}
+	for (int i = 0; key[i]; i++) {
+		key[i] = tolower(key[i]);
+	}
+
+	lenchain = strlen(chain);
+	lenkey = strlen(key);
+	
+	for (int i = 0; i < lenchain; i++) {
+		poskey = i % lenkey;
+
+		poschain = chain[i] - 'a';
+		poskey = key[poskey] - 'a';
+
+		//Text concatenation
+		postext = (poschain - poskey + 26) % 26;
+		text[textIndex++] = alphabet[postext];
+	}
+
+	text[textIndex] = '\0';
+
+	system("cls || clear");
+	printf("-======[ Vigenere cipher ]============-\n\n");
+	printf("\t- Vigenere ciphertext: %s\n", chain);
+	printf("\t- Key : %s\n", key);
+	printf("\t- Plaintext : %s\n", text);
+}
diff --git a/algorithms/roundrobin.c b/algorithms/roundrobin.c
index c3c88c52..75a62d1c 100644
--- a/algorithms/roundrobin.c
+++ b/algorithms/roundrobin.c
@@ -5,29 +5,29 @@ int main()
       int i, limit, total = 0, x, counter = 0, time_quantum;
       int wait_time = 0, turnaround_time = 0, arrival_time[10], burst_time[10], temp[10];
       float average_wait_time, average_turnaround_time;
-      printf("nEnter Total Number of Processes:t");
+      printf("\nEnter Total Number of Processes: ");
       scanf("%d", &limit);
       x = limit;
       for(i = 0; i < limit; i++)
       {
-            printf("nEnter Details of Process[%d]n", i + 1);
+            printf("\nEnter Details of Process[%d]\n", i + 1);
  
-            printf("Arrival Time:t");
+            printf("Arrival Time: ");
  
             scanf("%d", &arrival_time[i]);
  
-            printf("Burst Time:t");
+            printf("Burst Time: ");
  
             scanf("%d", &burst_time[i]);
  
             temp[i] = burst_time[i];
       }
  
-      printf("nEnter Time Quantum:t");
+      printf("\nEnter Time Quantum: ");
       scanf("%d", &time_quantum);
-      printf("nProcess IDttBurst Timet Turnaround Timet Waiting Timen");
+      printf("\nProcess ID\t\tBurst Time\t Turnaround Time\t Waiting Time\n");
       for(total = 0, i = 0; x != 0;)
-      {
+    {
             if(temp[i] <= time_quantum && temp[i] > 0)
             {
                   total = total + temp[i];
@@ -42,7 +42,11 @@ int main()
             if(temp[i] == 0 && counter == 1)
             {
                   x--;
-                  printf("nProcess[%d]tt%dtt %dttt %d", i + 1, burst_time[i], total - arrival_time[i], total - arrival_time[i] - burst_time[i]);
+                  printf("\nProcess [%d]\t\t%d\t\t %d\t\t\t %d", i + 1, 
+                burst_time[i], 
+              total - arrival_time[i], 
+              total - arrival_time[i] - burst_time[i]);
+              
                   wait_time = wait_time + total - arrival_time[i] - burst_time[i];
                   turnaround_time = turnaround_time + total - arrival_time[i];
                   counter = 0;
@@ -63,7 +67,8 @@ int main()
  
       average_wait_time = wait_time * 1.0 / limit;
       average_turnaround_time = turnaround_time * 1.0 / limit;
-      printf("nnAverage Waiting Time:t%f", average_wait_time);
-      printf("nAvg Turnaround Time:t%fn", average_turnaround_time);
+      printf("\n\nAverage Waiting Time: %.2f", average_wait_time);
+      printf("\nAvg Turnaround Time: %.2f\n", average_turnaround_time);
+      getchar();
       return 0;
 }