JAVA程序改错流程控制.ppt

1、题目1：计算1到100的整数和值,public class Prog1 /*FOUND*/public static void main (args)/*FOUND*/int n=100,sum=1; while(n0) sum+=n;/*FOUND*/n+;/*FOUND*/System.println(“Sum is “+sum); ,public static void main(String args ),int n=100,sum=0;,n-;,System.out.println(“Sum is “+sum);,题目：计算并输出100以内最大的10个能被3或7整除的自然数之和,pu

2、blic class Prog1 public static void main(String args)int k,s=0,mc=0;/*FOUND*/for (k=500;k0;k+) /*FOUND*/if (k%3 = 0 ,for (k=500;k0;k-),if (k%3 = 0 | k%7=0),s=s+k;,if (mc=10),/*FOUND*/if (mc=10)break; System.out.println(“Sum is “+s); ,题目：求100到200之间的素数，并以5个一行的形式显示在屏幕上,public class Prog1 /*FOUND*/publi

3、c static void main(args); int n=0,j; for(int i=101;ii-1) System.out.print(“ “+i); n+;,public static void main(String args),for( j=2;j=i-1;j+),if( i%j=0),System.out.println();,if( n=5 ) /*FOUND*/System.out.print(); n=0; System.out.println(); ,题目：水仙花是指其各位、十位和百位的立方和等于这个三位数本 身的数，求出所有的水仙花数,public class P

4、rog1 /*FOUND*/public static void (String args) int n,i,j,k; /*FOUND*/for(n=100,n1000,n+) /*FOUND*/i=n/10;j=n/10%10;k=n/100;/*FOUND*/if (n=i*i*i+j*j*j+k*k*k)System.out.print(n+“ “); System.out.println(); ,public static void main(String args),for(n=100;n1000;n+),i=n%10;,if (n=i*i*i+j*j*j+k*k*k),题目：计算并

5、输出500以内最大的10个素数之和,public class Prog1 public static void main(String args) int sum=0,n=0,j,num=500;/*FOUND*/while (num = 2) ,while (num=2) & (n10),break;,n+;,num-;,题目：在屏幕上输出如下图形,public class Prog1 public static void main(String args) int i,j;/*FOUND*/for (i=1;i4;i+)for(j=1;j=4-i;j+)System.out.print(“

6、 “);/*FOUND*/for (j=1;j=i-1;j+)System.out.print(“* “);/*FOUND*/System.out.print();,for (i=1;i=4;i+),for (j=1;j=2*i-1;j+),System.out.println();,for(j=1;j=i;j+),* * * * * * * * * * * * * * * * * * * * * * * * *,for (i=1;i=3;i+)/*FOUND*/for(j=1;ji;j+)System.out.print(“ “);for (j=1;j=7-2*i;j+)System.out

7、.print(“* “);System.out.println(); ,题目：计算斐波纳契数列的前20项，并以每行5项的形式输出。 (斐波纳契数列的第一项为0，第二项为1，其后各项依次为相临前两项之和，即0，1，1，2，3，5，8.),public class Prog1 public static void main(String args) int f1,f2,f3,i;/*FOUND*/f3=0;f2=1;/*FOUND*/System.out.println(f1+“ “+f2+“ “);for (i=3;i=20;i+)f3=f1+f2;System.out.print(f3+“ “

8、);/*FOUND*/if (i%5=0)System.out.println();f1=f2;/*FOUND*/f2=f1;,f1=0;,System.out.print(f1+“ “+f2+“ “);,if (i%5=0),f2=f3;, ,题目：某学校1990年在校生人数为2700,计划年增长率为10%。试计算出19912000年每年在校生人数,/*FOUND*/ public Prog1 public static void main(String args) int i;/*FOUND*/int n=2700,v=0.1;/*FOUND*/for (i=1991;i2000;i+)/

9、*FOUND*/n=n*v;System.out.println(i+“ 年在校生人数为 “+(int)n); ,public class Prog1,double n=2700,v=0.1;,for(i=1991;i=2000;i+),n=n*(1+v);,题目：判断键盘上输入的年份是否为闰年(闰年是指能被400整除的 年份或是能被100整除但不能被4整除的年份),import java.io.*; /*FOUND*/ public Prog1 public static void main(String args) throws IOExceptionint year;BufferedRe

10、ader buf;buf=new BufferedReader(new InputStreamReader(System.in);System.out.print(“请输入预判断的年份:“);/*FOUND*/year=Integer.parseInt(buf.readLine(); /*FOUND*/ if( (year%400=0) ,public class Prog1,year=Integer.parseInt(buf.readLine();,if( (year%400=0)|(year%100!=0)&(year%4=0),else,题目：求1到100的偶数之和，奇数之积,publi

11、c class Prog1 public static void main(String args)/*FOUND*/int i,j,sum=1;/*FOUND*/int product=1; for(i=1;i=100;i+)/*FOUND*/if (i%2!=0)sum+=i;else/*FOUND*/product=i; System.out.println(“偶数之和是 : “+sum);System.out.println(“奇数之积是 : “+product); ,int i,j,sum=0;,double product=1;,if (i%2=0),product*=i;,题目：

12、按照如下公式求自然数e的近似值，要求误差小于0.0001: e=1+1/1!+1/2!+1/3!+1/4!+.+1/n!+.,public class Prog1 /*FOUND*/public static void main(args); int i=1,j;/*FOUND*/double sum=1,fact=0; do fact=fact*i;/*FOUND*/sum=sum+fact;i+;/*FOUND*/ while (fact=0.0001); System.out.println(“自然数e的近似值为 : “+sum); ,public static void main(St

13、ring args),double sum=1,fact=1;,sum=sum+1/fact;, while (1/fact=0.0001);,题目：利用如下公式求圆周率的值,直到最后一项的值小于0.000001为止/4=1-1/3+1/5-1/7+.,public class Prog1 public static void main(String args) int i=1;/*FOUND*/boolean b=false;double sum=0,t;/*FOUND*/t=1/i; while (t=0.000001)if (b)sum=sum+t;elsesum=sum-t;/*FOU

14、ND*/b=not b; /*FOUND*/ i=i+1;t=1.0/i;,boolean b=true;,t=1.0/i; 或 t=1/(double)i,b=!b;,i=i+2;,System.out.println(“圆周率的近似值为 : “+4*sum); ,题目：求1!+2!+3!+.+10!,public class Prog1 public static void main(String args) /*FOUND*/ int i=-1;/*FOUND*/ int sum=0,fact=1;/*FOUND*/ while(i10);fact=fact*i;sum=sum+fact

15、;i+;/*FOUND*/end while System.out.println(“和值是 “+sum); ,int i=1;,double sum=0,fact=1;,while(i=10),题目：根据学生的考试的百分制成绩得出分数等级 (90100为A级，8089为B级，7079为C级，6069为D级，60分以下为E级),import java.io.*; public class Prog1 public static void main(String args) throws IOException int grade;/*FOUND*/ boolean str;BufferedRe

16、ader buf;buf=new BufferedReader(new InputStreamReader(System.in);System.out.print(“请输入考试成绩：“);str=buf.readLine(); /*FOUND*/ grade=Int.parseInt(str); System.out.print(“对应的级别为：“);/*FOUND*/ if (grade90)System.out.println(“A“); else if (grade=80)System.out.println(“B“);,String str;,grade=Integer.parseIn

17、t(str);,if (grade=90),else if (grade=70)System.out.println(“C“); else if (grade=60)System.out.println(“D“); /*FOUND*/otherwise System.out.println(“E“); ,else,题目：求键盘上输入的一个整数的所有因子，以5个一行的形式输出，并求出所有因子之和。（如果一个整数a能被整数b整除，则b是a的因子。）,import java.io.*; public class Prog1 public static void main(String args) t

18、hrows IOException int n,cn=0,sum=0;BufferedReader buf;buf=new BufferedReader(new InputStreamReader(System.in);System.out.print(“请输入一个整数：“);n=Integer.parseInt(buf.readLine(); System.out.println(n+“的所有因子如下：“); /*FOUND*/for(int k=1;kn;k+)/*FOUND*/if(n%k=0)System.out.print(k+“ “);cn+; /*FOUND*/if (cn/5=

19、0)System.out.println();,for(int k=1;k=n;k+),if(n%k=0),/*FOUND*/sum+=k;System.out.println();System.out.println(“所有因子和值是：“+sum); ,sum+=k;,if (cn%5=0),题目：输出1到100之间的所有完全数。（完全数是其所有因子 包括1但不包括该数本身）的和值等于该数自身的数）,public class Prog1 public static void main(String args) /*FOUND*/int n,sum=0;for (n=1;n=100;n+)/*

20、FOUND*/sum=sum;for(int k=1;kn;k+)/*FOUND*/if(n/k=0)sum+=k;/*FOUND*/if(sum=n)System.out.print(n+“t“); ,int n,sum;,sum=0;,if(sum=n),if(n%k=0),题目：求键盘上输入的两个整数的最大公约数,import java.io.*; public class Prog1 public static void main(String args) throws IOException int m,n,t,r,gys;BufferedReader buf;buf=new Buf

21、feredReader(new InputStreamReader(System.in);System.out.print(“请输入第一个整数:“);m=Integer.parseInt(buf.readLine(); System.out.print(“请输入第二个整数:“);n=Integer.parseInt(buf.readLine(); if(mn)t=m;m=n; /*FOUND*/n=m; if (m%n=0) /*FOUND*/gys=m;,n=t;,gys=n;,gys=m;,r=m%n;,else do /*FOUND*/r=m/n;m=n;n=r;while (r!=0)

22、; /*FOUND*/gys=n;System.out.println(“最大公约数是 “+gys); ,题目：打印输出如下图形：,public class Prog1 /*FOUND*/public static void main(args) int i,j; /*FOUND*/for (i=1;i5;i+)for(j=1;ji;j+)System.out.print(“ “); /*FOUND*/for (j=1;j=11-2*i;j-)System.out.print(“* “); /*FOUND*/System.out.print(); ,public static void mai

23、n(String args),for (i=1;i=5;i+),System.out.println();,for (j=1;j=11-2*i;j+),* * * * * * * * * * * * * * * * * * * * * * * *,题目：计算 1/1+1/2+1/3+.+1/100 的值,public class Prog1 public static void main( String args ) /*FOUND*/int sum=0.0; /*FOUND*/for(int i=1; i100; i+) /*FOUND*/sum+=1/i; /*FOUND*/System.

24、out.println( “sum=“,sum ); ,double sum=0.0;,for(int i=1; i=100; i+),System.out.println( “sum=“+sum );,sum+=1/(double)i; 或 sum+=1.0/i; 或 sum+=1.0/(double)i;,题目：从键盘上输入一个整数n，求比n大的最小的素数,import java.io.*; public class Prog1 public static void main(String args) throws IOExceptionint n,i;/*FOUND*/char b;Bu

25、fferedReader buf;buf=new BufferedReader(new InputStreamReader(System.in);System.out.print(“请输入一个整数:“);n=Integer.parseInt(buf.readLine(); don=n+1;b=true;for(i=2;in;i+)/*FOUND*/ if (n/i=0)b=false; /*FOUND*/continue;,boolean b;,if (n%i=0),while(b=false); 或 while(!b);,break;,/*FOUND*/while(b=true);System.out.println(“所求的素数是“+n); ,