"> int is_run(int year) { if ((year % 400 == 0) || (year % 4 == 0 && year % 100 != 0)) { return 1; } return 0; } int main() { int arr[12] = { 31,28,31,30,31,30,31,31,30,31,30,31 };//平年 int year = 0; int month = 0; int day = 0; while (scanf("%d%d%d", &year, &month, &d...