高响应比作业调度

#include <malloc.h>
#include <cstdio>
#include <cstring>
#define N 10
typedef struct table
{
	char name[8];		// 作业名
	float in_well;		// 进入输入井的时间
	float begin_run;	// 开始运行时间
	float run_time;		// 运行时间
	float end_run;		// 结束运行时间
	float turnover_time;// 周转时间 
}jobtable;

void init(jobtable job[], int n)
{
	int i, j;
	printf("input %d job information\n", n);
	printf("in_well run_time name\n");
	for(i = 0; i < n; ++ i)
	{
		scanf("%f %f %s", &job[i].in_well, &job[i].run_time, job[i].name);
		job[i].begin_run = 0.0;
		job[i].end_run = 0.0;
		job[i].turnover_time = 0.0;
	}
} 

void print(jobtable job[], int n)
{
	int i;
	printf("name  in_well  run_time  begin_run  end_run  turnover_time\n");
	for(i = 0; i < n; ++ i)
	{
		printf("%s\t%0.1f\t%0.1f\t", job[i].name, job[i].in_well, job[i].run_time);
		if(job[i].begin_run == 0.0 && job[i].end_run == 0.0 && job[i].turnover_time == 0.0)
		{
			printf("                                      \n");
		}
		else
		{
			printf("%9.1f%9.1f\t%0.1f\n", job[i].begin_run, job[i].end_run, job[i].turnover_time);
		}
	}
}

void swap(jobtable job[], int p, int q)
{
	float temp1;
	char temp2[8];
	strcpy(temp2, job[p].name);
	strcpy(job[p].name, job[q].name);
	strcpy(job[q].name, temp2);
	temp1 = job[p].in_well;
	job[p].in_well = job[q].in_well;
	job[q].in_well = temp1;
	temp1 = job[p].run_time;
	job[p].run_time = job[q].run_time;
	job[q].run_time = temp1;
}

// 模拟当前作业表的调度过程 
float response_ratio(jobtable job[], int n)
{
	int i, j, temp;
	float average_time, ratio1, ratio2;
	job[0].begin_run = job[0].in_well;
	job[0].end_run = job[0].begin_run + job[0].run_time;
	job[0].turnover_time = job[0].end_run - job[0].begin_run;
	average_time = job[0].turnover_time;
	for(i = 1; i < n; ++ i)
	{
		if(job[i].in_well <= job[i - 1].end_run)
		{
			j = i + 1;
			temp = i;
			ratio1 = 1 + (job[i - 1].end_run - job[i].in_well) * 1.0 / job[i].run_time;
			while(j < n && job[j].in_well <= job[i - 1].end_run)
			{
				ratio2 = 1 + (job[i - 1].end_run - job[j].in_well) * 1.0 / job[j].run_time;
				if(ratio2 > ratio1)
				{
					temp = j;
				}
				j ++;
			}
			if(temp != i)
			{
				swap(job, i, temp);
			}
		}
		job[i].begin_run = job[i - 1].end_run;
		job[i].end_run = job[i].begin_run + job[i].run_time;
		job[i].turnover_time = job[i].end_run - job[i].in_well;
		average_time = average_time + job[i].turnover_time;
	}
	
	return (average_time / n);
}

int main()
{
	int n;
	float ave_turnover_time;
	jobtable job[N];
	printf("input job numbers\n");
	scanf("%d", &n);
	if(n <= N)
	{
		printf("按照进入输入井的先后顺序初始化作业表\n");
		init(job, n);
		printf("initial station\n");
		print(job, n);
		ave_turnover_time = response_ratio(job, n);
		printf("termination station\n");
		print(job, n);
		printf("ave_turnover_time is : %.1f\n", ave_turnover_time);
	}
	else
	{
		printf("error!\n");
	}
	
	return 0;
}

/*
0 120 a
30 60 b 
90 15 c

*/