Logic for this math problem

Question

Before I get stinker replies for cross posting , let me tell that , i have been recommended to post this in this forum.
My problem is such:
I need to find a logic to implement the following :
In the floating point number , say , 1.0.. the Integral part will remain constant(1) but the decimal part has to get incremented by 1
1.1 +0.1
1.2+0.1
1.3+0.1
1.4+0.1
1.5 +0.1
1.6+0.1
1.7+0.1
1.8+0.1
1.9+0.1
1.10+0.1
1.2... But what I need here is 1.11 ,1.12
I need my programming logic to detect there needs to be a change in the increment value from 0.1 to 0.01 when I reach 1.1
and from 0.01 to 0.001 when i reach 1.111..so on,
please suggest..

Answer 1

you can't do it with a double,
since double d = 1.10d; will be treated as 1.1d
what you can do is treat the double as a String
public void test(){
String s1 = "1.9";
String s2 = "1.10";
String s3 = "1";
String s4 = "1.1";
System.out.println(increment(s1));
System.out.println(increment(s2));
System.out.println(increment(s3));
System.out.println(increment(s4));
public String increment(String d){
int pos = d.indexOf(".");
if (pos != -1){
if (d.charAt(d.length()-1) == 0)
return d.substring(0, d.length()-2) +
ength()-2) + "1";
String temp = d.substring(pos+1);
int num = Integer.parseInt(temp);
num++;
return d.substring(0, pos+1) + num;
else
return d + ".1";
}gives
1.10
1.11
1.1
1.2
I leave it to you to understand the logic...it's to
get you started..it does not check for all conditions
of the inputI think it is a Math with algorithm problem. Your solution is good, but you are using String functions so much. There is other solution, handling with numbers only.