求助初学者求助！用三目运算符怎么编程？

#include<stdio.h>
int main() {
int h, m, s;
char strs[4][11] = { "classroom","dormitory","canteen","on the way" };
char* res = strs[0];
scanf("%d:%d:%d", &h, &m, &s);
res = (h < 6 || h > 18 || h == 18 && (m || s)) ? strs[1] : res;
res = ((m || s) && (h == 6 || h == 12 || h == 17)) ? strs[2] : res;
res = (!m && !s && (h == 6 || h == 7 || h == 12 || h == 13 || h == 17 || h == 18)) ? strs[3] : res;
printf("%s", res);
return 0;
}