import java.util.Scanner; public class Prog8{ public static void main(String[] args){ System.out.print("求s=a+aa+aaa+aaaa+...的值，请输入a的值："); Scanner scan = new Scanner(System.in).useDelimiter("\\s*");//以空格作为分隔符 int a = scan.nextInt(); int n = scan.nextInt(); scan.close();//关闭扫描器 System.out.println(expressed(2,5)+add(2,5)); } //求和表达式 private static String expressed(int a,int n){ StringBuffer sb = new StringBuffer(); StringBuffer subSB = new StringBuffer(); for(int i=1;i<n+1;i++){ subSB = subSB.append(a); sb = sb.append(subSB); if(i<n) sb = sb.append("+"); } sb.append("="); return sb.toString(); } //求和 private static long add(int a,int n){ long sum = 0; long subSUM = 0; for(int i=1;i<n+1;i++){ subSUM = subSUM*10+a; sum = sum+subSUM; } return sum; } } |
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