public class HelloWorld{
public static void main(String[] args){
int num = 999;
int count = 0;
if (num>=0 && num<=999999999) {
for (count=0;num/=10;count++){
System.out.println("他是个"+count+"位的数");
}
}else{
System.out.println("输入有误!");
}
??????????????
它是个
public class HelloWorld{
public static void main(String[] args){
int num = 999;
int count = 0;
String numm = String.valueOf(num);
count = numm.length();
System.out.println("它是个" + count + "位的数!");
}
}
public class HelloWorld{
public static void main(String[] args){
int num = 999;
int count = 0;
if (num >= 0 && num <= 999999999){
while(num != 0){
count++;
num /= 10;
}
System.out.println("它是个" + count + "位的数!");
}
else
System.out.println("输入有误!");
}
}
for(;布尔条件;)
你的代码这个地方的结果是整型,不是布尔型;