int num = 999; int count = 0; if(num>=0&&num<=999999999){ num="" count="count+1;">=10);} count=count+1; System.out.println("它是个"+count+"位的数!");
int num = 999;
int count = 0;
int c = 1;
double aa;
do {
aa = num / c;
c *= 10;
count++;
} while (aa > 10);
System.out.println("它是个"+count+"位的数!");
num="" count="count+1;">=10);是什么?
没循环 代码也有问题