>>346 これならどうだ!
#include<stdio.h>

int main(void){
char buf[1024];
int sum=0, price;
FILE *fp;
char *filename="data.txt";

fp=fopen(filename, "r");
if(fp==NULL) return 1;

fgets(buf, sizeof(buf), fp); // 一行目は読み捨てる

while(fscanf(fp, "%*s %d円 %s", &price, buf)==2){
sum+=price;
}
fclose(fp);
printf("\n計 %d 円\n", sum);
return 0;
}