Round robin scheduling - picture[6-32]

Practice_10/roundRobin_1.c

@@ -0,0 +1,74 @@
+#include <stdio.h>
+
+#define N   4   // Process count
+
+typedef struct{
+    char pid[3];    //Process name
+    int bt;         //CPU Burst time
+    int rt;         //Remaining time
+    int ct;         //Completion time
+    int tat;        //Turnaround time
+    int wt;         //Waiting time
+} Process;
+
+int main(){
+    Process p[N] = {
+        {"P1", 6, 6, 0, 0, 0},
+        {"P2", 3, 3, 0, 0, 0},
+        {"P3", 1, 1, 0, 0, 0},
+        {"P4", 7, 7, 0, 0, 0}
+    };
+
+    int q;  //Time quantum
+    int cs; //Context switch time
+    printf("규정 시간량 입력 : ");
+    scanf("%d", &q);
+    printf("문맥 교환 시간 입력 : ");
+    scanf("%d", &cs);
+
+    int time = 0;
+    int done = 0;
+
+    printf("\n간트 차트 : \n");
+    while(done < N){
+        for(int i = 0; i < N; i++){
+            if(p[i].rt > 0){
+                int exec = (p[i].rt > q) ? q : p[i].rt;
+                int start = time;
+
+                time += exec;
+                p[i].rt -= exec;
+
+                if(p[i].rt == 0){
+                    p[i].ct = time;
+                    p[i].tat = p[i].ct;
+                    p[i].wt = p[i].tat - p[i].bt;
+                    done++;
+                    printf("| %s (%d~%d 완료) ", p[i].pid, time - exec, time);
+                }else{
+                    printf("| %s (%d~%d, 남은 %d) ", p[i].pid, start, time, p[i].rt);
+                }
+
+                if(done < N){ 
+                    printf("| CS (%d~%d) ", time, time + cs);
+                    time += cs; 
+                }
+            }
+        }
+    }
+    printf("|\n");
+
+    printf("\nProcess\tBT\tCT\tTAT\tWT\n");
+    int sumTAT = 0, sumWT = 0;
+    for(int i = 0; i < N; i++){
+        printf("%s\t%d\t%d\t%d\t%d\n", p[i].pid, p[i].bt, p[i].ct, p[i].tat, p[i].wt);
+        sumTAT += p[i].tat;
+        sumWT += p[i].wt;
+    }
+
+    printf("\n평균 반환시간 : %.2f\n", (float)sumTAT / N);
+    printf("평균 대기시간 : %.2f\n", (float)sumWT / N);
+
+    return 0;
+}
+