二、编程题
【分析】：编写程序时，通过按照题目的要求编程。main函数实现对文件的操作和数据的输入。
#include
#define N 100
int chang(char a[],int b[],int *n)
{int sign,k=-1,i;
*n=0;
if(a[0]= ='-') sign=1;
else sign=0;
for(i=0;a[i]!='\0';i++)
if(a[i]>='0'&&a[i]<='9')
b[++k]=a[i]-'0';
*n=k;
return sign;}
main()
{char str[N];
int num[N],i,j,sign,n;
FILE *fp;
if((fp=fopen("myf2.out","w"))= =NULL)
{printf("can't open the file!");
exit(0);}
for(j=0;j<2;j++)
{gets(str);
sign=chang(str,num,&n);
fprintf(fp,"sign=%d,",sign);
fprintf(fp,"b=(");
for(i=0;i<=n;i++)
fprintf(fp,"%2d",num[i]);
fprintf(fp,")\n");
}
fclose(fp);
}