Java Process Control Exercise--perpetual calendar

Java Process Control Exercise--perpetual calendar

Tags: Java into the pit tour

0x01. Print inverted triangle and positive triangle

    public static void main(String[] args) {        // TODO Auto-generated method stub        int i;        int j;                /**         *  要求：打印一个倒三角以及一个正三角         *  方法：双层循环         **/        for(i=3;i>0;i--) {            for(j=1;j<=i;j++) {                System.out.print("*");            }            System.out.println();        }        for(i=1;i<4;i++) {            for(j=1;j<=i;j++) {                System.out.print("*");            }            System.out.println();        }    }

Output:************

0x02.99 multiplication Table 1 (Zheng Li)

    public static void main(String[] args) {        // TODO Auto-generated method stub        /**         *  要求：打印九九乘法表         *  方法：双层循环         **/        for(int i = 1;i<=9;i++) {            for(int j = 1;j<=i;j++) {                System.out.printf("%d*%d=%-2d\t",j,i,i*j);            }            System.out.println();        }    }

Output:1*1=1   1*2=2   2*2=4   1*3=3   2*3=6   3*3=9   1*4=4   2*4=8   3*4=12  4*4=16  1*5=5   2*5=10  3*5=15  4*5=20  5*5=25  1*6=6   2*6=12  3*6=18  4*6=24  5*6=30  6*6=36  1*7=7   2*7=14  3*7=21  4*7=28  5*7=35  6*7=42  7*7=49  1*8=8   2*8=16  3*8=24  4*8=32  5*8=40  6*8=48  7*8=56  8*8=64  1*9=9   2*9=18  3*9=27  4*9=36  5*9=45  6*9=54  7*9=63  8*9=72  9*9=81  

0x03.99 Multiplication Table 2 (inverted)

  public static void Main (string[] args) {for (int i = 1; I <= 9;  ++i) {for (int j = 1; J <= 9; j + +) {if (J < i) {//Output space by "%2d*%2 =%-2d                "Decision System.out.print (" ");                } else {System.out.printf ("%d*%d=%-2d\t", I, J, I*j);        }} System.out.println (); }    }

Output：1*1=1   1*2=2   1*3=3   1*4=4   1*5=5   1*6=6   1*7=7   1*8=8   1*9=9           2*2=4   2*3=6   2*4=8   2*5=10  2*6=12  2*7=14  2*8=16  2*9=18                  3*3=9   3*4=12  3*5=15  3*6=18  3*7=21  3*8=24  3*9=27                          4*4=16  4*5=20  4*6=24  4*7=28  4*8=32  4*9=36                                  5*5=25  5*6=30  5*7=35  5*8=40  5*9=45                                          6*6=36  6*7=42  6*8=48  6*9=54                                                  7*7=49  7*8=56  7*9=63                                                          8*8=64  8*9=72                                                                  9*9=81                                                                

0x04. Perpetual calendar calendar4.1 Solution Ideas

Example 1: February 1900.

1. 1900 for common year, February for 28 days.
2. February 01 is 31 days from January 01 (30+1=31).
3. Every 7 days is 1 weeks, (31%7=3) so February 01 is Wednesday (Date[0] for Sunday).
4. Starting from No. 01, the loop output to 28 can be;

Example 2: April 1900.

1. 1900 is common year, February has 28 days.
2. April 01 is 90 days from January 01 (30+28+31+1=90).
3. Every 7 days is 1 weeks, (90%7=6) so April 01 is Saturday (Date[0] for Sunday).
4. Starting from No. 01, the loop output to 30 can be;

4.2 Algorithmic Thinking

1. Confirm that the input year is a leap years. If it is a leap year, the number of days in February is 29, otherwise 28 days.
2. The number of days to solve the input month distance from January 1, 1900;
3. Make sure that number No. 01 of the month is the day of the week;
4. Output from number No. 01 to the last day of the month.

4.3 Java code

Package Com.ryanjie.test0727;import Java.util.scanner;public class Calendar {/** * function: Determine if the input year is a leap years * @ PARAM year * @return */static Boolean leapyear (int year) {if (year% 400 = = 0 | | (year% 4 = = 0 && Year% 100! = 0))         {//is a leap year return true;        } else {//is common year return false;            }}//n Indicates the start year static final int N = 1900; /** * Function: First confirm the current month distance January 1, 1900 days, and then determine the month of No. 01 is the day of the week, * after the control output calendar * @param currentyear * @pa Ram Currentmonth */static void MonthCalendar (int currentyear,int currentmonth) {//Sumdays used to store a common        How many days int sumdays = 0;                 Store 12 months of days (no 0月, so month[0]=0) int month[] = {0,31,28,31,30,31,30,31,31,30,31,30,31};                        The January 01 of each year stored in 1900-11969 is the day of the week year[0] = 1 for the January 01, 1970 for the Monday for (int i = N;i < Currentyear;i + +) { Days is used to store a previous yearTotal number of days (366/365) int day = 365;                if (Leapyear (i)) {days + +;            Sumdays = Sumdays + days;            } else{sumdays = Sumdays + days;        }}//If it is a leap year, February is changed to number 29th if (leapyear (currentyear)) {month[2] = 29;        } for (int i=1;i<currentmonth;i++) {sumdays = sumdays + month[i];        }//week used to store the current month number No. 01 is the day of the week Int week;                Week = (sumdays + 1)% 7;        System.out.println ("Sunday \ T" + "Monday \ T" + "Tuesday \ T" + "Wednesday \ T" + "Thursday \ T" + "Friday \ T" + "Saturday \ t");        System.out.println ();        Output control for (int i = 0;i < week; i++) {System.out.print ("\ t");            } for (int i = 1; I <= month[currentmonth]; i + +) {System.out.printf ("%-2d \ T", I);            if ((week)% 7 = = 6) {System.out.println ();        } week + +; }} PublIC static void Main (string[] args) {while (true) {int. Month, year;            Scanner in = new Scanner (system.in);            System.out.println (); SYSTEM.OUT.PRINTLN ("******** welcome you to use the perpetual calendar!"            ********");            System.out.println ("Please enter the year <1900~11900>:");            Year = In.nextint ();                if (year < 1900) {System.out.println ("Enter years is not legal, please re-enter!");            Year = In.nextint ();            } System.out.println ("Please enter month <1~12>:");            Month = In.nextint ();  if (Month < 1 | | |                Month > {System.out.println ("Enter the month is not legal, please re-enter!");            Month = In.nextint ();            } MonthCalendar (Year,month);            System.out.println (); System.out.println ("******** Thank you for using the perpetual calendar!        ********"); }           }}

Output:********欢迎您使用万年历！********请输入年份<1900~11900>:2018请输入月份<1~12> :7星期日 星期一 星期二     星期三     星期四     星期五     星期六       1       2       3       4       5       6       7       8       9       10      11      12      13      14      15      16      17      18      19      20      21      22      23      24      25      26      27      28      29      30      31    ********感谢您使用万年历！********

Emmm ..... The output format is correct, but the markdown format will be wrong, headache ....

Java Process Control Exercise--perpetual calendar