所以我正在进行调度，包括FCFS和Shortest Job First。我真的在最短的工作中苦苦挣扎，我无法看到我的逻辑错误。我把它打印出来，有些数字是正确的，但不是全部。我使用的测试文件包含以下文本：
1 0 6
2 3 2
3 5 1
4 9 7
5 10 5
6 12 3
7 14 4
8 16 5
9 17 7
10 19 2
我使用＆lt;命令只是在测试时将输入重定向到来自文件，所以./a.out < test.txt。
任何帮助，指针或代码都会非常感激！
编辑我认为我的问题是基于sfj函数的逻辑。对于输入，第一列是进程ID，第二列是到达时间，第三列是突发时间或进程需要多长时间与cpu。
我得到的输出是：
Shortest Job First
PID WAIT TURNAROUND
1 0 6
2 15 17
3 3 4
4 0 7
5 6 11
6 9 12
7 10 14
8 12 17
9 16 23
10 21 23
Average Wait: 9 Average Turnaround 13
当我真正期待：
Shortest Job First
Pid Wait Turnaround
1 0 6
2 4 6
3 1 2
4 0 7
5 15 20
6 4 7
7 7 11
8 14 19
9 18 25
10 0 2
Average wait: 6.3 Average turnaround: 10.5
// File.c
// Project6
//
// Created by Chris on 6/19/14.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <termios.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/types.h>
#define LINELEN 512
#define MAX_PROCESS 100
typedef struct process
{
int ID;
int arrival_time;
int time_to_completion;
int wait_time;
int turn_around;
int active;
}process;
void fcfs(struct process[MAX_PROCESS], int);
void sjf (struct process[MAX_PROCESS], int);
void srtn(struct process[MAX_PROCESS], int);
void rr (struct process[MAX_PROCESS], int);
void rrc(struct process[MAX_PROCESS], int);
void print_info(struct process[MAX_PROCESS], int);
void sort_by_time(struct process array[MAX_PROCESS], int num_valid_pid);
int main(int ac,char *av[])
{
int counter=0;
int p1=0, p2=0, p3=0;
process array[MAX_PROCESS];
while ( scanf("%d %d %d", &p1, &p2, &p3) != EOF ){//Get all the info available and put it in array of structs
array[counter].ID = p1;
array[counter].arrival_time = p2;
array[counter].time_to_completion = p3;
counter++;
}
fcfs(array, counter);
sjf (array, counter);
/*srtn(array, counter);
rr (array, counter);
rrc(array, counter);*/
return 0;
}
void fcfs(struct process array[MAX_PROCESS], int num_pid){
//for loop num_pid
int i;
int current_time = 0;
for(i=0; i<num_pid; i++){
//if arrival is < current time, wait time = current time - arrival
if(array[i].arrival_time < current_time)
array[i].wait_time = current_time - array[i].arrival_time;
//if arrival is >= current time, wait time = 0;
else if(array[i].arrival_time >= current_time)
array[i].wait_time = 0;
//current time = current time + wait time + time to completion
current_time= current_time + array[i].time_to_completion;
//turnaround time = wait time + time to completion
array[i].turn_around = array[i].wait_time + array[i].time_to_completion;
}
printf("First Come First Serve\n");
print_info(array, num_pid);
}
void sjf (struct process array[MAX_PROCESS], int num_pid){
printf("Shortest Job First\n");//for the output so we know what algorithm
//create an array of pids that are valid to search.
int num_valid_processes = 0, current_time=0, i,j, next_process, counter = 0;//declarations
process to_sort[MAX_PROCESS];
//we want to do this next loop for as many processes as we have, or num_pid
for(j=0; j<num_pid; j++){
//adds all the available processes to the to sort array to be sorted
//available means that it has arrived, which means it is <= current_time
//after it gets all the processes, it breaks out of the for loop
for(i=counter; i<num_pid; i++){
if(array[i].arrival_time<=current_time){
to_sort[i]=array[i];
num_valid_processes++;
counter++;
}
else
break;
}
//sort the to_sort array by the time_to_completion
sort_by_time(to_sort,num_valid_processes);
//set the wait time and turnaround time for the next process
next_process = to_sort[0].ID;
array[next_process].wait_time = current_time-array[next_process].arrival_time;
array[next_process].turn_around = array[next_process].wait_time + array[next_process].time_to_completion;
//change the current_time and continue
//current time = current time + wait time + time to completion
current_time= current_time + array[next_process].time_to_completion;
//delete the process we just worked on so we don't get duplicates.
num_valid_processes--;
for(i=0;i<num_valid_processes;i++){
to_sort[i]=to_sort[i+1];
}
}
//loop back up to get available processes
//now all the info in out first array is filled out, print it out.
print_info(array, num_pid);
}
void print_info(struct process array[MAX_PROCESS], int num_pid){
int i;
int tot_wait=0, tot_turn = 0;
printf("\x1b[04mPID\tWAIT\tTURNAROUND\n\x1b[24m");
for(i=0; i<num_pid; i++){
printf("%d\t%d\t%d\n", array[i].ID, array[i].wait_time, array[i].turn_around);
tot_wait=tot_wait+array[i].wait_time;
tot_turn = tot_turn +array[i].turn_around;
}
printf("Average Wait: %d Average Turnaround %d\n", tot_wait/num_pid, tot_turn/num_pid);
}
void sort_by_time(struct process array[MAX_PROCESS], int num_valid_pid)
{
int i,j;
for (i = 0; i < num_valid_pid; i++)
{
int min = i;
for (j = i+1; j < num_valid_pid; j++)
if (array[j].time_to_completion < array[min].time_to_completion)
min = j;
process temp = array[i];
array[i] = array[min];
array[min] = temp;
}
}
答案 0 :(得分：0)
问题最终出现在sjf函数中，for循环的赋值不正确，应该是
for(i=counter; i<num_pid; i++){
if(array[i].arrival_time<=current_time){
to_sort[num_valid_process]=array[i];
num_valid_processes++;
counter++;
}
...