//输入一个正整数,输出2000年1月1日经过该整数天后的日期.已测试,输入值可以为0~1095727//如,100天后,日期为2000 4 10#include#define MAX_YEAR 5000//年数可以从2000一直到4999年。//函数功能:求解第year年共有多少天int day_in_year(int year){ if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) return 366; else return 365;}int main(){ int input; int year, month, day; long Accumulate_days_for_year[MAX_YEAR] = {0}; int Accumulate_days_for_month_in_leap_year[13] = {0,31,29,31,30,31,30,31,31,30,31,30,31}; int Accumulate_days_for_month_in_aver_year[13] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; int i; scanf_s("%d", &input); for (i = 2000; i < MAX_YEAR; i++) { Accumulate_days_for_year[i] = day_in_year(i); } for (i = 2001; i < MAX_YEAR; i++) { //该数组[2000]为366;[2001]为366+365,即2000年和2001年天数的累和;[2002]为366+365+365,即2000-2002年天数的累和。依次类推。 //通过将累和与输入input比较,即可得知结果为哪一年。 Accumulate_days_for_year[i] = Accumulate_days_for_year[i - 1] + Accumulate_days_for_year[i]; } for (i = 2; i < 13; i++) { //该数组[1]为31;[2]为31+29,即1月和2月天数的累和;[3]为31+29+31,即1-3月天数的累和。依次类推。 //通过累和判断结果为哪一月。 Accumulate_days_for_month_in_leap_year[i] = Accumulate_days_for_month_in_leap_year[i] + Accumulate_days_for_month_in_leap_year[i - 1]; //该数组[1]为31;[2]为31+28,即1月和2月天数的累和;[3]为31+28+31,即1-3月天数的累和。依次类推。 //通过累和判断结果为哪一月。 Accumulate_days_for_month_in_aver_year[i] = Accumulate_days_for_month_in_aver_year[i] + Accumulate_days_for_month_in_aver_year[i - 1]; } //判断年数 for (i = 2000; i < MAX_YEAR; i++) { if (input < Accumulate_days_for_year[i]) { year = i; break; } } //得知年数后,通过下式判断结果为当年的第几天。 input = input - Accumulate_days_for_year[year-1]; //如果year为闰年,使用月累和数组Accumulate_days_for_month_in_leap_year if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) { for (i = 1; i < 13; i++) { if (input < Accumulate_days_for_month_in_leap_year[i]) { month = i; day = input - Accumulate_days_for_month_in_leap_year[i - 1] + 1; break; } } } //如果year为平年,使用月累和数组Accumulate_days_for_month_in_aver_year else { for (i = 1; i < 13; i++) { if (input < Accumulate_days_for_month_in_aver_year[i]) { month = i; day = input - Accumulate_days_for_month_in_aver_year[i - 1] + 1; break; } } } printf("%d\n", year); printf("%d\n", month); printf("%d\n", day); return 0;}