Java编程.pdf

求两个数的平均数 平方根 平方 packagepackage shixun importimport java util Scanner publicpublic classclass Shixun1 publicpublic staticstatic voidvoid main String args Scanner sc newnew Scanner System in doubledouble a sc nextDouble doubledouble b sc nextDouble doubledouble c a b 2 doubledouble d1 Math sqrt a doubledouble d2 Math sqrt b doubledouble c0 a a System out println c t d1 t d2 t c0 packagepackage shixun 输出a b及其ASCII publicpublic classclass Shixun2 publicpublic staticstatic voidvoid main String args charchar x1 a intint x2 97 intint y2 x1 1 charchar y1 charchar y2 System out println x1 t x2 t y1 t y2 判断三个数的最大数 packagepackage shixun importimport java util Scanner publicpublic classclass Shixun3 publicpublic staticstatic voidvoid main String args Scanner sc newnew Scanner System in intint a sc nextInt intint b sc nextInt intint c sc nextInt intint max a ifif a b ifif a c max a elseelse max c elseelse ifif b c max b elseelse max c System out print max packagepackage shixun 显示200以内能被5或6整除 但不能被两者同时整除的数 publicpublic classclass Shixun4 publicpublic staticstatic voidvoid main String args intint k 0 forfor intint i 1 i 200 i ifif i 5 0 k ifif k 5 0 System out println packagepackage shixun 1 到10 publicpublic classclass Shixun5 publicpublic staticstatic voidvoid main String args intint i 1 j 1 sum 0 dodo j j i sum sum j i whilewhile i 10 System out println sum 编程实现简易计算器 根据 运算符 对两数执行相应的运算 packagepackage shixun importimport java util Scanner publicpublic classclass Shixun6 publicpublic staticstatic voidvoid main String args Scanner input newnew Scanner System in System out print 请输入第一个操作数 doubledouble num1 input nextInt System out print 请输入第二个操作数 doubledouble num2 input nextInt System out print 运算符 String fuHao input next charchar c fuHao charAt 0 doubledouble num3 0 switchswitch c casecase num3 num1 num2 breakbreak casecase num3 num1 num2 breakbreak casecase num3 num1 num2 breakbreak casecase num3 num1 num2 breakbreak defaultdefault System out println 输入符号错误 System out println num1 fuHao num2 num3 判断21世纪闰年的个数 packagepackage shixun publicpublic classclass Shixun7 publicpublic staticstatic voidvoid main String args intint k 0 forfor intint i 2000 i 2100 i ifif i 400 0 i 4 0 k ifif k 5 0 System out println System out println 21世纪闰年的个数为 k 对输入的数遇到9999停止输入并显示之前数的和 packagepackage shixun importimport java util Scanner publicpublic classclass Shixun8 publicpublic staticstatic voidvoid main String args intint sum 0 intint a Scanner sc newnew Scanner System in whilewhile a sc nextInt 9999 sum a System out println sum packagepackage shixun classclass MyCal intint sum intint m intint s 0 forfor intint i 1 i 100 i s i returnreturn s intint sum intint m intint n intint t 0 ifif m n forfor intint i m in forfor intint i n i m i t i returnreturn t publicpublic staticstatic voidvoid main String args MyCal cc newnew MyCal System out println 1到100的和为 cc sum 100 System out println 25到60的和为 cc sum 25 60 System out println 60到78的和为 cc sum 78 60 利用Triangle类 求三条边长分别为2 5 3 5 4的三角形的周长和面积 packagepackage shixun classclass Triangle doubledouble a b c Triangle doubledouble x doubledouble y doubledouble z a x b y c z doubledouble getL returnreturn a b c doubledouble getS doubledouble p a b c 2 doubledouble s Math sqrt p p a p b p c returnreturn s publicpublic staticstatic voidvoid main String args System out println newnew Triangle 2 5 3 5 4 getL System out println newnew Triangle 2 5 3 5 4 getS 设计一个类Triangle 分别将三角形的三条边作为属性 并能计算面积 默认为勾三股四弦五的直角三角形 一个参数时默认为等边三角形 三个参数时分别为三条边长 packagepackage shixun classclass Triangle1 doubledouble i doubledouble j doubledouble k Triangle1 doubledouble a i j k a doubledouble p 3 a 2 doubledouble s Math sqrt p p a p a p a System out print 这是一个边长为 a 的等边三角形 System out println 面积是 s Triangle1 doubledouble x doubledouble y doubledouble z i x j y k z doubledouble p i j k 2 doubledouble s Math sqrt p p i