華為2012校園招聘機(jī)試java題

1、將大寫字母轉(zhuǎn)換成其對(duì)應(yīng)小寫字母后的第五個(gè)字母，大于z的從頭開(kāi)始數(shù)。publicclassTest1{publicCharacterupperToLower(Characterc){charch=(char)(c.charValue()+32+5);if(ch>'z'){ch-=26;}returnch;}publicstaticvoidmain(String[]args){Test1test1=newTest1();System.out.println(test1.upperToLower('A'));System.out.println("************************");System.out.println(test1.upperToLower('W'));}}2、將一個(gè)十進(jìn)制數(shù)（byte類型）轉(zhuǎn)化二進(jìn)制數(shù)，將二進(jìn)制數(shù)前后顛倒，再算出顛倒后其對(duì)應(yīng)的十進(jìn)制數(shù)。publicclassTest2{publicbytechange(byteb){int[]input=newint[8];intk=0;while(b/2!=0){input[k]=b%2;b/=2;k++;}input[k]=b%2;for(inti=0;i<input.length/2;i++){inttemp=input[i];input[i]=input[input.length-1-i];input[input.length-1-i]=temp;}//intsum=0;//for(inti=0;i<input.length;i++){//sum+=(int)(input[i]*Math.pow(2,i));//}intsum=input[0];for(inti=1;i<input.length;i++){intmid=input[i];for(intj=0;j<i;j++){mid*=2;}sum+=mid;}//System.out.println(sum);return(byte)sum;}publicstaticvoidmain(String[]args){Test4test4=newTest4();System.out.println(test4.change((byte)5));}}3、大數(shù)相乘publicclassTest3{publicStringmutiStr(Stringstr1,Stringstr2){Stringresult=null;//存放結(jié)果字符串//確定負(fù)號(hào)intflagStr1=0;if(str1.startsWith("-")){flagStr1++;}intflagStr2=0;if(str2.startsWith("-")){flagStr2++;}//*********************************************************************//將數(shù)字放到整數(shù)數(shù)組，逆序，字符串尾部對(duì)齊int[]arrStr1=newint[str1.length()-flagStr1];for(inti=0;i<arrStr1.length;i++){arrStr1[i]=str1.charAt(str1.length()-1-i)-'0';}int[]arrStr2=newint[str2.length()-flagStr2];for(inti=0;i<arrStr2.length;i++){arrStr2[i]=str2.charAt(str2.length()-1-i)-'0';}//***********************************************************************//運(yùn)算開(kāi)始，arrStr2的每位去乘arrStr1的每位StringBuffersubResult=newStringBuffer();//中間結(jié)果for(inti=0;i<arrStr2.length;i++){StringBuffermidResult=newStringBuffer();//每位結(jié)果intintsubBenWei=subJinWei=0;//每位相乘時(shí)的本位上數(shù)字0;//每位相乘時(shí)的進(jìn)位上數(shù)字for(intk=0;k<i;k++){midResult.append(0);//先添加0，確保每位末尾對(duì)齊，便于加法運(yùn)算}for(intj=0;j<arrStr1.length;j++){subBenWei=(arrStr2[i]*arrStr1[j]+subJinWei)%10;subJinWei=(arrStr2[i]*arrStr1[j]+subJinWei)/10;midResult.append(subBenWei);if((j==arrStr1.length-1)&&subJinWei>0){midResult.append(subJinWei);//果添加進(jìn)位數(shù)字}}if(0==i){subResult=midResult;//第一位，子結(jié)果存放第一位結(jié)果}else{//各位對(duì)齊，確保中間結(jié)果和每位結(jié)果位數(shù)相同，便于相加運(yùn)算if(midResult.length()>subResult.length()){intdiff=midResult.length()-subResult.length();while(diff>0){subResult.append(0);diff--;}}else{intdiff=subResult.length()-midResult.length();while(diff>0){midResult.append(0);diff--;}}//*********************************************************//相加運(yùn)算，結(jié)果放到subResult中intbenWei=0;intjinWei=0;for(intj=0;j<subResult.length();j++){benWei=((subResult.charAt(j)-'0')+(midResult.charAt(j)-'0')+jinWei)%10;jinWei=((subResult.charAt(j)-'0')+(midResult.charAt(j)-'0')+jinWei)/10;subResult.setCharAt(j,(char)(benWei+'0'));}//如果最后相加任有進(jìn)位，結(jié)果中添加進(jìn)位if(jinWei>0){subResult.append(jinWei);}//***********************************************************}“-”

}//判斷“-”的個(gè)數(shù)，沒(méi)有或有兩個(gè)則為結(jié)果為正，不考慮，如只有一個(gè)則結(jié)果要添加if(1==(flagStr1+flagStr2)){subResult.append('-');}resultsubResult.reverse().toString()//最終子結(jié)果逆序，即為結(jié)果returnresult;}publicstaticvoidmain(String[]args){//TODOAuto-generatedmethodstubStringBuffersb=newStringBuffer();// Stringstr1="99999999999";// Stringstr2="99999999999";for(in