13、 以下程序是统计一组数据中正数的和、正数的个数；零的个数；负数的和,负数的个数.数据以-999为结束

//data file name is ddd.dat;
#include
#include
main(){
FILE *fp;
int t,tag,z,f,l,sz,sf;
if((fp=fopen("ddd.dat","r"))==NULL)exit(1);
while(!feof(fp)){
fscanf(fp,"%d",&t);
if(t==-999)exit(2);
if(t>0)tag=1;
else if(t==0)tag=0;
else tag=-1;
switch(tag){
case 1:z++;sz+=t;break;
case 0:l++;break;
case -1:f++;sf+=t;break;
}
fclose(fp);
printf("%d Positive numbers are amount to %d\n" z;sz);
printf("%d Negative numbers are amount to %d\n" f;sf);
printf("%d Zero numbers \n",l);
}