MV_81 - 1 year ago 48

Java Question

I need to create a method that finds intervals within an array that add up to 13

example:

{10,0,3,0,1,1,1,10,5,5,5}

0 and 2 add to 13

0 and 3 add to 13

3 and 7 add to 13

4 and 7 add to 13

EDIT: this is the output I'm getting

interval 0 and 2 is 13

interval 0 and 6 is 13

interval 2 and 9 is 13

This is what I tried:

`public static void findSum (int[] arr) {`

int i = 0;

int j = 1;

int resu = 0;

while (i < arr.length-1) {

if (resu == 13) {

j++;

}

resu = arr[i] + arr[j];

while (j < arr.length-1 && resu < 13){

j++;

resu = resu + arr[j];

}

if (resu == 13){

System.out.println("interval " + i + " and " + j + " is 13");

}

if (resu != 13){

i++;

}

}

}

Answer Source

I think you had some issues with declaring variables in wrong places as well as unnecessary conditional statements. This should do it for you..

```
public static void findSum (int[] arr) {
int i = 0;
while (i < arr.length-1) {
//define resu and j on the inside as these change with every i
//start j from the i+1
int j = i+1;
//define resu as the ith element
int resu = arr[i];
//keep adding to resu until we have reached end of array or until resu is greater than the target
while (j < arr.length-1 && resu < 14){
//add the jth element of the array
resu = resu + arr[j];
//print if we have a match
if (resu == 13){
System.out.println("interval " + i + " and " + j + " is 13");
}
j++;
}
i++;
}
}
```