JavaSE part1 基礎程式設計day06
阿新 • • 發佈:2018-11-03
4_1
程式碼:
public static void main(String[] args) { Scanner scanner=new Scanner(System.in); int positiveCount=0;//正數個數 int negativeCount=0;//負數個數 int sum=0;//總和 double average=0;//平均值 System.out.print("Enter an integer,the input ends if it is 0:"); while(true){ int num=scanner.nextInt(); if(num<0){ negativeCount++; }else if(num>0){ positiveCount++; }else{ break; } sum=sum+num; } average=1.0*sum/(negativeCount+positiveCount); System.out.println("The number of positive is "+positiveCount); System.out.println("The number of negative is "+negativeCount); System.out.println("The total is "+sum); System.out.println("The average is "+average); }
4_2
程式碼:
public static void main(String[] args){ Scanner scanner=new Scanner(System.in); int firstScore=0,secondScore=0; String firstName="",secondName=""; System.out.print("Enter the number of the students:"); int count=scanner.nextInt(); System.out.print("Enter the name and score:"); for(int i=0;i<count;i++){ String name=scanner.next(); int score=scanner.nextInt(); if(score>=firstScore){ secondScore=firstScore; secondName=firstName; firstScore=score; firstName=name; }else if(score>=secondScore){ secondScore=score; secondName=name; } } System.out.println(firstName+" : "+firstScore); System.out.println(secondName+" : "+secondScore); }
4_3
程式碼:
public static void main(String[] args){
int count=0;
for(int i=100;i<=200;i++){
if(i%5==0||i%6==0&&i%5==0^i%6==0){
System.out.print(i+" ");
count++;
if(count%10==0){
System.out.println();
}
}
}
}
4_4
程式碼:
public static void main(String[] args) { int n=1; while(n*n<=12000){ n++; } System.out.println(109*109); System.out.println(n); n=1; while(n*n*n<=12000){ n++; } System.out.println(n*n*n); System.out.println(n-1); System.out.println(22*22*22); }
4_5
程式碼:
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);
System.out.print("Enter a number:");
int number=scanner.nextInt();
while(true){
boolean flag=false;
for(int i=2;i<number/2;i++){
if(number%i==0){
System.out.print(i+" ");
number/=i;
flag=true;
break;
}
}
if(!flag){
System.out.print(number);
break;
}
}
}
4_6
程式碼:
public static void main(String[] args){
Scanner scanner=new Scanner(System.in);
System.out.print("Enter the line:");
int line=scanner.nextInt();
for(int i=1;i<=line;i++){
for(int k=1;k<=line-i;k++){
System.out.print(" ");
}
for(int j=-i;j<=i;j++){
if(j!=0&&j!=1){
System.out.printf("%-3d",Math.abs(j));
}
}
System.out.println();
}
}
4_8
程式碼:
public static void main(String[] args){
Scanner scanner=new Scanner(System.in);
System.out.print("Enter the line:");
int line=scanner.nextInt();
for(int i=1;i<=line;i++){
for(int k=1;k<=line-i;k++){
System.out.print(" ");
}
for(int j=-(i-1);j<=i-1;j++){
if(j<=0){
System.out.printf("%-4d",(int)Math.pow(2,j+i-1));
}else{
System.out.printf("%-4d",(int)Math.pow(2,-j+i-1));
}
}
System.out.println();
}
}
ScanneDemo:
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);
//無論使用者輸入的是什麼資料 都以字串先獲取
System.out.print("Enter:");
//"10 20"->"10""20"->"10"->double
String a=scanner.next();//返回的是第一個字串
double b=scanner.nextDouble();
String c=scanner.next();
System.out.println(a+b+c);
//"1 2 3 4"
System.out.println(Integer.parseInt("abc"));
//"10 20 30 回車"
scanner.nextLine();//吃掉回車
System.out.print("Enter line:");
String s=scanner.nextLine();
System.out.println("["+s+"]");
}