阅读下面的语句块,1.StringBufferSb=newStringBuffer("abc");2.StringS=newString("abc");3.Sb.append("def");4.S.append("def");5.Sb.insert(1,"ghi");6.S.concat(sb);编译出错的有哪几行 A: 2 B: 3 C: 4 D: 6

下面哪些语句是没有编译错误的（） A: StringBuffersb=“java”； B: inti=0x56； C: Booleanb=newBoolean（“java”）； D: floatf=1.0；

请阅读下面程序 publicclassExampleStringBuffer publicstaticvoidmain(String[]args) StringBuffersb=newStringBuffer("test")； System.out.println("buffer-，"+sb)； System.out.println("longth="+sb.1ength())； 程序运行结果中在“length”后输出的值是( )。 A: 10 B: 4 C: 20 D: 30

下列关于字符串的描叙中错误的是（ ）。 A: 字符串是对象 B: 可以使用StringBuffersb="这里是字符串"声明并初始化StringBuffer对象sb C: String类提供了许多用来操作字符串的方法：连接，提取，查询等

写出下面程序的输出结果 publicclassTestjava{ publicstaticvoidmain(String[]args){ Strings1="abcdefhij"; Strings2=""; char[]cs=s1.toCharArray(); for(inti=cs.length-1;i>=0;i--){ s2=s2+cs[i]; } System.out.println("输出的结果1:"+s2); StringBuffersb=newStringBuffer(s1); StringBuffersb2=sb.reverse(); System.out.println("输出的结果2:"+sb2); Strings3=myReverse(s1); System.out.println("输出的结果3:"+s3); } publicstaticStringmyReverse(Stringstr) { char[]arr=newchar[str.length()]; intpos=str.length(); for(intx=0;x[/i]

下列关于字符串的描叙错误的是（） A: 字符串是对象 B: String对象存储字符串的效率比StringBuffer高 C: 可以使用StringBuffersb="这里是字符串"声明并初始化StringBuffer对象sb D: String类提供了许多用来操作字符串的方法：连接，提取，查询等

for i in range(b.max_row): for j in range(b.max_column): print(b.cell(row=i,column=j).value)上面语句运行的结果是：__________。 A: 1 1 1 1 1 1 1 1 1 1 B: 1111111111 C: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 D: 出现异常

【单选题】CDMA通信的基站,假定基站A的码片序列是+1 +1 +1 -1 -1 +1 -1 -1,基站发射bit为101时,实际发射的信号是 A. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 B. +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 +1 +1 +1 -1 -1 +1 -1 -1 C. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 D. –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1

for i in range(1,11): for j in range(1,11): b.cell(row=i,column=j).value=1 #b是一个工作表对象for i in range(1,11): for j in range(1,11): print(b.cell(row=i,column=j).value,end=" ") print()上面程序代码运行的结果是（）。 A: 1 B: 1 1 1 1 1 1 1 1 1 1 C: 1111111111 D: 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1

下列哪个码片序列不能用于CDMA通信 A: ( -1 -1 -1 +1 +1 -1 +1 +1 ) B: ( -1 -1 +1 -1 +1 +1 +1 -1 ) C: ( -1 +1 -1 +1 +1 -1 -1 -1 ) D: ( -1 +1 -1 -1 -1 -1 +1 -1 )