从键盘输入1～7（否则应给出出错信息）之间的数字，输出表示一个星期中对应某一天的英文单词。

#include <stdio.h>

#define DAYS_OF_WEEK 7

char *day[DAYS_OF_WEEK] =
{
"monday",
"tuesday",
"wendsday",
"thirsday",
"friday",
"saturday",
"sunday"
};

int main(void)
{
int i;

scanf("%d", &i);

if (i < 1 || i > DAYS_OF_WEEK)
{
printf("You've entered a wrong day\n");
return -1;
}

printf("The day is %s\n", day[i-1]);

return 0;
}