Question

java从键盘输入三角形的三条边，判断它们能否构成三角形。若能构成三角形，指出是何种三角形？

Answer 1

这样写

package com;
import java.util.Scanner;

public class W
{

	public static void main(String[] args){
		System.out.println("请输入三边以逗号隔开");
		Scanner sc = new Scanner(System.in);
		String location1 = sc.next();
		String[] location1s = location1.split(",");
		int x1 = Integer.parseInt(location1s[0]);
		int y1 = Integer.parseInt(location1s[1]);
		int z1 = Integer.parseInt(location1s[2]);
		
		if((x1+y1>z1)&&(x1+z1>y1)&&(y1+z1>x1)){
			System.out.println("能构成三角形");
		}else{
			System.out.println("不能构成三角形");
		}
		
	}
}

Answer 2

public static void main(String[] args) {
		
		int i=0;
		double sides[]={0L,0L,0L};
		
			do{System.out.println("input the sides:");
			Scanner sc=new Scanner(System.in);
			for(i=0;i<3&&sc.hasNext();i++){
				try{
				sides[i]=Double.parseDouble(sc.next());
				}catch(NumberFormatException e){
					e.printStackTrace();
				}
			}
			if(i!=3) System.out.println("input three sides please!");
		}while(i!=3);
		Arrays.sort(sides);
		if((sides[0]+sides[1])>sides[2]){
			String trianType="";
			if(sides[0]*sides[0]+sides[1]*sides[1]>sides[2]*sides[2]){
				if(sides[0]==sides[2]&&sides[0]==sides[1]){
					trianType="equilateral ";
				}else{
					trianType="acute ";
				}
			}else if(sides[0]*sides[0]+sides[1]*sides[1]<sides[2]*sides[2]){
				trianType="obtuse ";
			}else{
				trianType="right ";
			}
			if((sides[0]==sides[1]||sides[1]==sides[2])&&sides[0]!=sides[2])
				trianType+="isosceles ";
			System.out.println("those make a "+trianType+" triangle");
		}else{
			System.out.println("those don't make a triangle");
		}

	}

Answer 3

package com.hello;
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class hello{
public static void main(String[] args){
try{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("请输入长度X:");
String x=br.readLine();
System.out.println("请输入长度Y:");
String y=br.readLine();
System.out.println("请输入长度Z:");
String z=br.readLine();

int t;
int a = Integer.parseInt(x);
int b = Integer.parseInt(y);
int c = Integer.parseInt(z);

if(a>b){t=0; t=b; b=a; a=t;}
if(a>c){t=0; t=c; c=a; a=t;}
if(b>c){t=0; t=c; c=b; b=t;}

if(a+b >= c && a!= 0 && b!=0 && c!=0){
System.out.println("构成三解形");
if(a==b || a==c){
System.out.println("构成等腰三解形");
}
if(a==b && a==c){
System.out.println("构成等边三解形");
}
}
else
{
System.out.println("输入值不构成三解形");
}
}
catch(Exception e){}
}
}