scheduling algorithms added

scheduling_algorithms/fcfs_scheduling.c

@@ -0,0 +1,42 @@
+#include <stdio.h>
+
+int main()
+{
+    int n, bt[20], wt[20], tat[20];
+    float avg_wt = 0, avg_tat = 0;
+
+    printf("Enter number of processes: ");
+    scanf("%d", &n);
+
+    printf("Enter Burst Times:\n");
+    for (int i = 0; i < n; i++)
+    {
+        printf("P%d: ", i + 1);
+        scanf("%d", &bt[i]);
+    }
+
+    wt[0] = 0;
+    for (int i = 1; i < n; i++)
+        wt[i] = wt[i - 1] + bt[i - 1];
+
+    for (int i = 0; i < n; i++)
+        tat[i] = bt[i] + wt[i];
+
+    for (int i = 0; i < n; i++)
+    {
+        avg_wt += wt[i];
+        avg_tat += tat[i];
+    }
+
+    avg_wt /= n;
+    avg_tat /= n;
+
+    printf("\nProcess\tBT\tWT\tTAT\n");
+    for (int i = 0; i < n; i++)
+        printf("P%d\t%d\t%d\t%d\n", i + 1, bt[i], wt[i], tat[i]);
+
+    printf("\nAverage Waiting Time = %.2f", avg_wt);
+    printf("\nAverage Turnaround Time = %.2f\n", avg_tat);
+
+    return 0;
+}

scheduling_algorithms/priority_scheduling.c

@@ -0,0 +1,69 @@
+#include <stdio.h>
+
+int main()
+{
+    int n, bt[20], p[20], pr[20], wt[20], tat[20];
+    float avg_wt = 0, avg_tat = 0;
+    int i, j, pos, temp;
+
+    printf("Enter number of processes: ");
+    scanf("%d", &n);
+
+    printf("Enter Burst Time and Priority:\n");
+    for (i = 0; i < n; i++)
+    {
+        printf("P%d\n", i + 1);
+        printf("Burst Time: ");
+        scanf("%d", &bt[i]);
+        printf("Priority: ");
+        scanf("%d", &pr[i]);
+        p[i] = i + 1;
+    }
+
+    // Sort by Priority (lower number = higher priority)
+    for (i = 0; i < n; i++)
+    {
+        pos = i;
+        for (j = i + 1; j < n; j++)
+        {
+            if (pr[j] < pr[pos])
+                pos = j;
+        }
+        temp = pr[i];
+        pr[i] = pr[pos];
+        pr[pos] = temp;
+        temp = bt[i];
+        bt[i] = bt[pos];
+        bt[pos] = temp;
+        temp = p[i];
+        p[i] = p[pos];
+        p[pos] = temp;
+    }
+
+    wt[0] = 0;
+    for (i = 1; i < n; i++)
+    {
+        wt[i] = 0;
+        for (j = 0; j < i; j++)
+            wt[i] += bt[j];
+        avg_wt += wt[i];
+    }
+
+    for (i = 0; i < n; i++)
+    {
+        tat[i] = bt[i] + wt[i];
+        avg_tat += tat[i];
+    }
+
+    avg_wt /= n;
+    avg_tat /= n;
+
+    printf("\nProcess\tBT\tPriority\tWT\tTAT\n");
+    for (i = 0; i < n; i++)
+        printf("P%d\t%d\t%d\t\t%d\t%d\n", p[i], bt[i], pr[i], wt[i], tat[i]);
+
+    printf("\nAverage Waiting Time = %.2f", avg_wt);
+    printf("\nAverage Turnaround Time = %.2f\n", avg_tat);
+
+    return 0;
+}

scheduling_algorithms/round_robin_scheduling.c

@@ -0,0 +1,68 @@
+#include <stdio.h>
+
+int main()
+{
+    int n, bt[20], rem_bt[20], wt[20], tat[20], quantum;
+    int t = 0, i;
+    float avg_wt = 0, avg_tat = 0;
+
+    printf("Enter number of processes: ");
+    scanf("%d", &n);
+
+    printf("Enter Burst Times:\n");
+    for (i = 0; i < n; i++)
+    {
+        printf("P%d: ", i + 1);
+        scanf("%d", &bt[i]);
+        rem_bt[i] = bt[i];
+        wt[i] = 0;
+    }
+
+    printf("Enter Time Quantum: ");
+    scanf("%d", &quantum);
+
+    int done;
+    while (1)
+    {
+        done = 1;
+        for (i = 0; i < n; i++)
+        {
+            if (rem_bt[i] > 0)
+            {
+                done = 0;
+                if (rem_bt[i] > quantum)
+                {
+                    t += quantum;
+                    rem_bt[i] -= quantum;
+                }
+                else
+                {
+                    t += rem_bt[i];
+                    wt[i] = t - bt[i];
+                    rem_bt[i] = 0;
+                }
+            }
+        }
+        if (done == 1)
+            break;
+    }
+
+    for (i = 0; i < n; i++)
+    {
+        tat[i] = bt[i] + wt[i];
+        avg_wt += wt[i];
+        avg_tat += tat[i];
+    }
+
+    avg_wt /= n;
+    avg_tat /= n;
+
+    printf("\nProcess\tBT\tWT\tTAT\n");
+    for (i = 0; i < n; i++)
+        printf("P%d\t%d\t%d\t%d\n", i + 1, bt[i], wt[i], tat[i]);
+
+    printf("\nAverage Waiting Time = %.2f", avg_wt);
+    printf("\nAverage Turnaround Time = %.2f\n", avg_tat);
+
+    return 0;
+}

scheduling_algorithms/sjf_scheduling.c

@@ -0,0 +1,65 @@
+#include <stdio.h>
+
+int main()
+{
+    int n, bt[20], p[20], wt[20], tat[20];
+    float avg_wt = 0, avg_tat = 0;
+    int i, j, pos, temp;
+
+    printf("Enter number of processes: ");
+    scanf("%d", &n);
+
+    printf("Enter Burst Times:\n");
+    for (i = 0; i < n; i++)
+    {
+        printf("P%d: ", i + 1);
+        scanf("%d", &bt[i]);
+        p[i] = i + 1;
+    }
+
+    // Sort by Burst Time
+    for (i = 0; i < n; i++)
+    {
+        pos = i;
+        for (j = i + 1; j < n; j++)
+        {
+            if (bt[j] < bt[pos])
+                pos = j;
+        }
+        temp = bt[i];
+        bt[i] = bt[pos];
+        bt[pos] = temp;
+        temp = p[i];
+        p[i] = p[pos];
+        p[pos] = temp;
+    }
+
+    wt[0] = 0;
+    for (i = 1; i < n; i++)
+        wt[i] = 0;
+
+    for (i = 1; i < n; i++)
+    {
+        for (j = 0; j < i; j++)
+            wt[i] += bt[j];
+        avg_wt += wt[i];
+    }
+
+    for (i = 0; i < n; i++)
+    {
+        tat[i] = bt[i] + wt[i];
+        avg_tat += tat[i];
+    }
+
+    avg_wt /= n;
+    avg_tat /= n;
+
+    printf("\nProcess\tBT\tWT\tTAT\n");
+    for (i = 0; i < n; i++)
+        printf("P%d\t%d\t%d\t%d\n", p[i], bt[i], wt[i], tat[i]);
+
+    printf("\nAverage Waiting Time = %.2f", avg_wt);
+    printf("\nAverage Turnaround Time = %.2f\n", avg_tat);
+
+    return 0;
+}