How to extract integers from a separated string in java

Question

Examples of the String

131-5923-213
1421-41-4-12-4
1-1

How would I extract the integers into an Array or find the sum of these integers? My code so far goes

int hyphenCount = socialNum.length()-socialNum.replaceAll("-", "").length();

ArrayList<Integer> sum = new ArrayList<Integer>();
for(int i = 0; i < hyphenCount; i++)
{
   //my brain is too small             
}

What I want to do is make a function like the following

public void extractSum(String s)
{
  int outputSum;

  //stuff

  return outputSum;
}

https://stackoverflow.com/questions/3481828/how-to-split-a-string-in-java#3481842 — 4dc0, Nov 09 '18 at 03:11
`Arrays.stream(inputString.split("-")).mapToInt(Integer::parseInt).sum();` ? — Jai, Nov 09 '18 at 03:13
Is the "sum" of `131-5923-213` meant to be `131 + 5923 + 213 = 6267`, or `1 + 3 + 1 + 5 + 9 + 2 + 3 + 2 + 1 + 3 = 30`? — Kevin Anderson, Nov 09 '18 at 03:20

GBlodgett · Answer 1 · 2018-11-09T03:25:03.013

0

Using Streams you can do:

int sum = Arrays.stream(str.replace("-",  "").split("")).mapToInt(Integer::valueOf).sum();

Which will replace the hyphen and then split each character, parse the integer, and return the sum

Output: (For the String "131-5923-213")

If you want the sum of 131 + 5923 + 213 you could do:

int sum = Arrays.stream(str.split("-")).mapToInt(Integer::valueOf).sum();

Which will split on a hyphen, parse the integers, and return the sum

edited Nov 09 '18 at 03:25

answered Nov 09 '18 at 03:14

GBlodgett

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I think the OP is asking `131 + 5923 + 213 = 6267` – Kartik Nov 09 '18 at 03:23
@Kartik I edited in a solution for that – GBlodgett Nov 09 '18 at 03:25

score 0 · Answer 2 · answered Nov 09 '18 at 03:49

Apart from @GBlodgett's answer using stream, you could simply run a for loop to calculate the sum.

String string = "131-5923-213";

String[] num = string.split("-");  //<----num[0] = "131" ,num[1]="5923",num[2] = "213"

int hyphenCount = num.length;  //<----it would give you 3 as length

int mySum = 0;   //initialize the sum as 0

for(int i = 0; i < hyphenCount; i++)
{
     mySum+= Integer.parseInt(num[i]); //<---convert the string to an int

}

Output: 6267

How to extract integers from a separated string in java

2 Answers2