P2433 【深基1-2】小学数学 N 合一

题意：

解决六个问题：

反思：

对于浮点数，可以假如是100/3. 最好以100/3.0输出的时候，手动保留 3 到4位最好。

AC

package Main6; import java.io.*; import java.util.*; public class Main6 { public static void main(String[] args) { Scanner cin = new Scanner(System.in); int n = cin.nextInt(); int ans1 ,ans2, ans3 ; if(n==1) { System.out.println("I love Luogu!"); }else if(n==2){ ans1 = 6; ans2 = 4; System.out.println(ans1+" "+ans2); }else if(n==3){ ans1 = 3; ans2 = 12; ans3 = 2; System.out.println(ans1 + "\n" + ans2 + "\n" + ans3); }else if(n==4){ double a = 500.0/3; System.out.println(String.format("%.3f",a)); //本题是要求保留三位有效数字，！！！！！！ }else if(n==5){ ans1 = 15; System.out.println(ans1); }else if(n==6){ double a = Math.sqrt(6*6+9*9); System.out.println(String.format("%.4f", a)); }else if(n==7){ System.out.println(110); System.out.println(90); System.out.println(0); }else if(n==8){ final double PI = 3.141593;//Math.acos(-1.0); double a1 = PI*5*2; double a2 = PI*25; double a3 = (4/3.0*PI*125); System.out.println(String.format("%.4f", a1)); System.out.println(String.format("%.4f", a2)); System.out.println(String.format("%.3f", a3)); }else if(n==9){ ans1 = 1; for(int i=1; i<=3; i++) { ans1++; ans1*=2; } System.out.println(ans1); }else if(n==10){ System.out.println(9); }else if(n==11){ double a = 100.0/3.0; System.out.println(String.format("%.4f", a)); }else if(n==12){ char ch='A'; char cha = 'A'; ans1 = 0; for(int i=0; i<26; i++) { if((char)(ch+i)=='M') { ans1 = i; } if(i == 17) cha = (char)(ch+i); } ans1++; System.out.println(ans1); System.out.println(cha); }else if(n==13){ final double PI = 3.141593;//Math.acos(-1.0); double a1 = 4/3.0*PI*10*10*10; double a2 = 4/3.0*PI*4*4*4; ans1 = (int)Math.pow(a1+a2,1.0/3); System.out.println(ans1); }else { System.out.println(50); } } }