（1）建立C程序 mymax.c 如下：
double mymax(double*ary,int n)
{
int i;
double themax = ary[0];
for(i=0;i<n;i++)
if(themax<ary[i])
themax = ary[i];
return themax;
}
（2）建立C程序 mymin.c 如下：
doublemymin(double *ary,int n)
{
int i;
double themin = ary[0];
for(i=0;i<n;i++)
if(themin>ary[i])
themin = ary[i];
return themin;
}
（3）建立C程序 mysum.c 如下：
doublemysum(double *ary,int n)
{
int i;
double thesum = 0;
for(i=0;i<n;i++)
thesum += ary[i];
return thesum;
}
（4）建立C程序 myavg.c 如下：
doublemyavg(double *ary,int n)
{
int i;
double theavg = 0;
if(n==0)
return 0;
for(i=0;i<n;i++)
theavg += ary[i];
return theavg/n;
}
（5）建立C程序 my.h 如下：
doublemymax(double *,int);
doublemymin(double *,int);
doublemysum(double *,int);
doublemyavg(double *,int);
（6）建立C程序 mymain.c 如下：
#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#include<my.h>
intmain(void)
{
double *data;
int num=0;
int n;
while(num<=0)
{
printf("Please input the number ofthe array:");
scanf("%d",&num);
}
data = (double*)malloc(n*sizeof(double));
if(data == NULL)
{
printf("memory error!\n");
exit(-1);
}
n=0;
while(n<num)
{
printf("Please inputarray[%d]:",n);
scanf("%lf",data+n);
n++;
}
printf("The maximum of the arrayis:%f\n",mymax(data,num));
printf("The minimum of the arrayis:%f\n",mymin(data,num));
printf("The sum of the array is:%f\n", mysum(data,num));
printf("The average of the arrayis:%f\n",myavg(data,num));
}
（7）建立静态库libmylib.a
[root@localhostmylib]#gcc -c mymax.c mymin.c mysum.c myavg.c
[root@localhostmylib]# ar crv libmylib.a mymax.o mymin.o mysum.o myavg.o
（8）编译mymain.c程序
[root@localhost mylib]# gcc -omymain mymain.c -I. -L. –lmylib
（9）执行mymain程序
[root@localhost mylib]# ./mymain
Pleaseinput the number of the array:-5
Pleaseinput the number of the array:0
Pleaseinput the number of the array:5
Pleaseinput array[0]:123
Pleaseinput array[1]:234
Pleaseinput array[2]:345.99
Pleaseinput array[3]:456.88
Pleaseinput array[4]:678.345
Themaximum of the array is:678.345000
Theminimum of the array is:123.000000
The sumof the array is:1838.215000
Theaverage of the array is:367.643000
