First Come First Serve Algorithm | Gantt Chart | Waiting Time | Turn Around Time

fcfs.c

//
// Created by xenon on 18/9/18.
//
#include<stdio.h>
#include<stdbool.h>

struct Input
{
    char ProcessId[100];
    int at, bt;
};

void input(int num, struct Input *process)
{
    printf("\n\nEnter Details Of Process %d: ", num);

    printf("\nProcess Name : ");
    scanf("%s", process->ProcessId);
    printf("Enter Arrival Time : ");
    scanf("%d", &process->at);
    printf("Enter Burst Time : ");
    scanf("%d", &process->bt);
}

int main()
{
    struct Input obj[100];
    int choice, processNum, prevTime = 0;

    printf("\nEnter The Number Of Process : ");
    scanf("%d", &processNum);

    for(int i=0; i<processNum; i++)
    {
        input(i, &obj[i]);
    }

    while(true)
    {
        printf("\n1. Gantt Chart\n2. Waiting Time\n3. Turn Around Time\n4. Exit\nChoice : ");
        scanf("%d", &choice);

        if (choice == 1)
        {
            printf("\n\nGantt Chart:\n");
            for(int i=0; i<processNum; i++)
            {
                if (obj[i].at >= prevTime)
                {
                    printf("%d", obj[i].at);

                    for(int j=0; j<obj[i].bt; j++)
                    {
                        printf("*");
                    }

                    prevTime = prevTime + obj[i].bt;
                }

                else
                {
                    printf("%d", prevTime);
                    for(int j=0; j<obj[i].bt; j++)
                    {
                        printf("*");
                    }
                    prevTime = prevTime + obj[i].bt;
                }
            }
            printf("%d\n\n", prevTime);
            prevTime = 0;
        }

        else if(choice == 2)
        {
            printf("\n\nWaiting Time:\nProcess Number\t\tWaiting Time\n");
            for(int i=0; i<processNum; i++)
            {
                if (obj[i].at >= prevTime)
                {
                    printf("%s\t\t\t%d\n", obj[i].ProcessId, 0);

                    prevTime = prevTime + obj[i].bt;
                }

                else
                {
                    printf("%s\t\t\t%d\n", obj[i].ProcessId, prevTime-obj[i].at);

                    prevTime = prevTime + obj[i].bt;
                }
            }
            prevTime = 0;
        }

        else if(choice == 3)
        {
            printf("\n\nTurn Around Time:\nProcess Number\t\tTurn Around Time\n");
            for(int i=0; i<processNum; i++)
            {
                if (obj[i].at >= prevTime)
                {
                    printf("%s\t\t\t%d\n", obj[i].ProcessId, obj[i].bt);

                    prevTime = prevTime + obj[i].bt;
                }

                else
                {
                    printf("%s\t\t\t%d\n", obj[i].ProcessId, prevTime-obj[i].at+obj[i].bt);

                    prevTime = prevTime + obj[i].bt;
                }
            }
            prevTime = 0;
        }
        else if(choice == 4)
        {
            break;
        }
        else
        {
            printf("\nInvalid Input!\nTry Again\n");
        }
    }
}