#include<stdio.h>
int add(int x,int y,int z);
int total;
int sum=0;
int main(void)
{
    FILE *fp;
    int i,j,k,n,x,y,z;
    fp=fopen("data.dat","r");
    if(fp==NULL)
    {
        printf("open file failed!\n");
        exit(1);
    }
    while (!feof(fp))
    {
        n=fscanf(fp,"%d %d %d",&x,&y,&z);
        if(3==n) //这句很重要,因为feof()是根据字节来判断的,而'\0'为两个字节很可能多循环一次,所以要检查参数
        {
            sum=add(x,y,z);
            total++;
        }
    }
    printf("sum=%d\ntotal %d numbers\n",sum,total);
    return 0;
}
int add(int x,int y,int z)
{
    sum+=x+y+z;
    return sum;
}