>>19
#include<stdio.h>

#define SUBJECT_NUM 5

int main(void)
{
int i, total=0;
double average;
int score[SUBJECT_NUM];
char *subject_name[SUBJECT_NUM]={"英語", "数学", "国語", "理科", "社会"};

for(i=0;i<SUBJECT_NUM;i++)
{
printf("%sの点数を入力してください\n", subject_name[i]);
scanf("%d", &score[i]);
if(score[i]==100) printf("さすが\n");
else if(score[i]<40) printf("ひどい\n");
}

for(i=0;i<SUBJECT_NUM;i++) total+=score[i];
average=(double)total/SUBJECT_NUM;

printf("合計 %d 平均 %.1f\n", total, average);

return 0;
}