以一道簡單題區分String,StringBuffer類,及其簡單應用
阿新 • • 發佈:2018-11-14
我感覺java離我越來越遠了,嗚嗚嗚嗚,剛開始對String類 與StringBuffer類(據說StringBuilder更好),對多種類之間的方法糅合在一起應用,這很重要,下面以一道題為例子(c,java均有):
幾個基本方法:
1.char charAt(int index)返回字串中的字元;
2.StringBuf reverse() 字串反轉 如:123asd —dsa321
例題:
c語言程式碼(定義變數較多,便於理解):
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int num = scanner.nextInt();
int t=num;
int digit=0;
int sum=0,m=0;
while(num!=0){
digit++;
m=num%10;
sum=sum*10+m;
num/=10;
}
num= t;
System.out.printf("%d\n",digit);
String s=String.valueOf(num);
int n=sum;
while(sum!=0){
m=sum%10;
if(m==sum/Math.pow(10,digit-1))
{
System.out.printf("%d",m);
break;
}
System. out.printf("%d ",m);
sum/=10;
}
System.out.printf("\n");
System.out.printf("%d\n",n);
}
}
java語言(方便)
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String s = sc.next();
StringBuffer s2 = new StringBuffer();;
System.out.printf("%d\n",s.length());
for(int i=0;i<s.length();i++) {
s2.append(s.charAt(i));
if(i==s.length()-1) {
System.out.println(s.charAt(i));
break;
}
System.out.printf("%c ",s.charAt(i));
}
System.out.println(s2.reverse());
}
}