SRTF.txt

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>


int n,g=0,at[10],bt[10],gantt[50],wtgstate[10];


int main(){
	
	int i,j,t,x,srt,min,sum_bt=0;
	
	printf("Enter no of processes: ");
	scanf("%d",&n);
	
	printf("\nEnter ATs for all processes: ");  //assuming user inputs sorted ATs in increasing order and AT for the first process is 0
	for(i=0;i<n;i++){
		scanf("%d",&at[i]);
	}
	
	printf("\nEnter BTs for all processes: ");
	for(i=0;i<n;i++){
		scanf("%d",&bt[i]);
	}
	
	
	
	for(i=0;i<n;i++){
		sum_bt+=bt[i];
		wtgstate[i]=0;
	}
	gantt[g++]=0;
	bt[0]--;
	srt=bt[0];
	wtgstate[0]=2;
	for(t=1;t<sum_bt;t++,g++){
		//printf("(%d,%d)",gantt[g-1],bt[gantt[g-1]]);
		//is some process arriving?
		for(i=0;i<n;i++){
			if(wtgstate[i]==0){
				if(at[i]==t){	//found one => process needs to be changed to waiting
					wtgstate[i]=1;
					if(bt[i]<srt){	//is its BT less than the RTs of ones in waiting?
						x=i;
						srt=bt[i];
					}
					break;
				}
			}
			
		}
		//pulling the SRT one out if found

		if(srt<bt[gantt[g-1]]){	//if the one in queue has SRT than the one in gantt
			wtgstate[gantt[g-1]]=1;
			gantt[g]=x;
			wtgstate[x]=2;
			bt[x]--;
			//assigning srt to the least one n waiting state
			min=1000;
			for(i=0;i<n;i++){
				if(wtgstate[i]==1){
					if(bt[i]<min){
						min=bt[i];
						x=i;
					}
					
				}
			}
			srt=min;
		}
		else{
			gantt[g]=gantt[g-1];
			bt[gantt[g]]--;
		}
		
		if(bt[gantt[g]]==0){
			wtgstate[gantt[g]]=-1;		//process executed
			bt[gantt[g]]=1000;
		}
		
	}

	for(i=0;i<g;i++){
		printf("P%d|",gantt[i]+1);
	}
	
	return (0);
}