Question

统计出从1到1000每个数字出现的次数,用java编写

Answer 1

public class Count{
public static void main(String args[]){
int count[]=new int[10];//记录个数
for(int i=1;i<=1000;i++)
{
String s=String.valueOf(i);
for(int j=0;j<10;j++)
{
if(s.contains(String.valueOf(j)))
count[j]+=1;
}
}
for(int i=0;i<10;i++)
{
System.out.println(i+"出现的次数是："+count[i]);
}
}
}

Answer 2

public class TestCount {
public static void main(String args[]){
int count0 = 0;
int count1 = 0;
int count2 = 0;
int count3 = 0;
int count4 = 0;
int count5= 0;
int count6 = 0;
int count7 = 0;
int count8 = 0;
int count9 = 0;
StringBuffer sf = new StringBuffer();
String [] arr = new String [1000];
for(int i =0;i<1000;i++){
arr[i] =Integer.toString(i+1);
sf.append(arr[i]);
}
System.out.println(sf.length());
for(int i =0;i<sf.length();i++){
if(sf.charAt(i)=='0'){
count0++;
}
else if(sf.charAt(i)=='1'){
count1++;
}
else if(sf.charAt(i)=='2'){
count2++;
}
else if(sf.charAt(i)=='3'){
count3++;
}
else if(sf.charAt(i)=='4'){
count4++;
}
else if(sf.charAt(i)=='5'){
count5++;
}
else if(sf.charAt(i)=='6'){
count6++;
}
else if(sf.charAt(i)=='7'){
count7++;
}
else if(sf.charAt(i)=='8'){
count8++;
}
else if(sf.charAt(i)=='9'){
count9++;
}
}
System.out.println("有"+count0+"个0");
System.out.println("有"+count1+"个1");
System.out.println("有"+count2+"个2");
System.out.println("有"+count3+"个3");
System.out.println("有"+count4+"个4");
System.out.println("有"+count5+"个5");
System.out.println("有"+count6+"个6");
System.out.println("有"+count7+"个7");
System.out.println("有"+count8+"个8");
System.out.println("有"+count9+"个9");
}
}

Answer 3

2楼精辟