+ 7

I can't understand this code, so please can anyone explain me it?

int [ ] myArr = {6, 42, 3, 7}; int sum=0; for(int x=0; x<myArr.length; x++) { sum += myArr[x]; } System.out.println(sum); Output = 58 what does that myArr [x] does? and what is that += means?

12th Dec 2016, 1:52 AM
Ryan Luisen
20 Answers
+ 21
šŸ˜„ it's gonna be a long day, but let's figure it out! in first round of for loop x=0, so myArr[x] is myArr[0]=6, sum=0 +6 so sum is 6 now round 2 x=1, so myArr[x] is myArr[1]=42, sum=6 +42 sum is 48 now round 3 x=2, so myArr[x] is myArr[2]=3, sum=48+3 sum is 51 now round 4, final round x=3, so myArr[x] is myArr[3]=7, sum=51+7 so final sum value 58
12th Dec 2016, 2:59 AM
Morpheus
Morpheus - avatar
+ 13
myArr[x] is used to get all the elements of this array using for loop.myArr[0] means the value '6',myArr[1] means the value '42' and so on.'myArr.length' returns the length or size of this array(here the size is 4) and check whether x<size(inside for loop).Also,inside the for loop, x is assigned with 0,when it runs it check that x<myArr.length (here 0<4),which is true.As it is true it will go inside the for loop and do what ever according to the statement.Here, sum+=myArr[x],same as sum=sum+myArr[x] which means, sum=0+myArr[0] sum=0+6 sum=6 i.e. stored in the variable sum. After this the for loop will update the value of x(i.e. x++),now the value of x turns to 1 and 1<4,which is true.Then get inside the loop, sum=6+myArr[1] sum=6+42 sum=48 Again,the loop will update the value of x and x will be 2,checks x<4 i.e.2<4,which is true,then sum=sum+myArr[2] sum=48+3 sum=51 Next,the value of x will be updated to 3 which is also less than 4.Then, sum=sum+myArr[3] sum=51+7 sum=58,we get the answer. After this the value of x is updated again and become x=4,when checking the condition 4<4 which is false and the for loop is terminated. Then outside the for loop,the statement to print sum will display the sum as, 58 That's all!!!!!!!!
12th Dec 2016, 3:13 AM
Sreerag V S
Sreerag V S - avatar
+ 5
i got it..... Thanks Neetish Raj You are the best!
12th Dec 2016, 2:55 AM
Ryan Luisen
+ 4
so how does the output comes out 58? and what does that myArr [x] does?
12th Dec 2016, 2:31 AM
Ryan Luisen
+ 4
thanks Sreerag but already understod
12th Dec 2016, 3:56 AM
Ryan Luisen
+ 3
myArr is your one dimensional integer array , consisting of 4 elements , see below with their position no.s in array , it always start from 0 array elements 6 42 3 7 position 0 1 2 3 x+=y is just a short notation for x=x+y, that's it similarly x-=y is x=x-y x/=y is x=x/y for * and % also applicable
12th Dec 2016, 2:22 AM
Morpheus
Morpheus - avatar
+ 3
sorry but still i am not understanding what x does in myArr [x]
12th Dec 2016, 2:38 AM
Ryan Luisen
+ 3
ok , myArr is just a list , used to store items, and their numbering for position. begins with 0 so if u want to access some value in that array list , this is the notation to access it myarr[x] where depending on the value of x that element is chosen so if x is 0 then first element of myArr x is 1 then second element and so on
12th Dec 2016, 2:44 AM
Morpheus
Morpheus - avatar
+ 2
all elements of myArr are added 6+42+3+7=58 elements of array are accessed using position no.s myArr[0] is 6 myArr[1] is 42 and so on till 4th element using for loop value of x is changed from 0, 1,2, and 3 , hence myArr[x] access all elements of array and keep adding them into sum variable
12th Dec 2016, 2:36 AM
Morpheus
Morpheus - avatar
+ 2
ya
12th Dec 2016, 2:39 AM
Ryan Luisen
+ 2
woudn't that then output 7, what i understand = An array with the type int is assigned these values, 6, 42, 3, 7 an variable named sum with the type int is assigned the value 0 type int variable x = 0, if the x (0) is less than the length of the array (4) sum (0) = sum (0) + myArr [x] (0) [ this line is confusing] print the 'sum'
12th Dec 2016, 2:51 AM
Ryan Luisen
+ 2
Thank you both of you! now i can proceed! šŸ˜€šŸ‘
12th Dec 2016, 3:59 AM
Ryan Luisen
+ 2
Sorry but this discussion is closed, so no need of answering it. thankyou for your kindness!
8th Jan 2017, 4:35 AM
Ryan Luisen
+ 1
Question: what does that myArr [x] does? Answer: It means to start counting from 0 to the number of elements of myArr. myArr have 4 elements: 6, 42, 3 and 7. In other words it's 0 < 4, 0-3 or 4 numbers. First will have to add all 4 elements 6+42+3+7 to get 58. Question: and what is that += means? Answer: It means to add the total of numbers to the variable sum. sum is 0 and all 4 elements of myArr is 58. In other words you will add myArr to sum or 0+58=58.
7th Jan 2017, 4:36 PM
David Oats
David Oats - avatar
0
šŸ˜…šŸ¤˜
12th Dec 2016, 3:58 AM
Morpheus
Morpheus - avatar
0
Till all elems in myArr are iterated, sum = sum + myArr[0], first iteration, sum is 6 sum = sum + myArr[1], second iteration, sum is 6+ 42 sum = sum + myArr[2], third iteration, sum is 6+42+3 sum = sum + myArr[3], fourth iteration, sum is 6+42+3+7 condition fails exit; prints sum
7th Jan 2017, 7:28 PM
boy
0
could anyone explain me this snippet print ("sum : " + sum); i am able to understand the function but this statement. function sumOfIntegers(int n) { int i, sum = 0; // declare the variables i, sum for (i = 1; i <= n; ++i) { // loop through till satisfies the condition i <= n sum += i; // sum = sum + i } print ("sum : " + sum); }
1st Jun 2018, 8:13 PM
gurpreet arora
gurpreet arora - avatar
0
var count = 0 item myArr{ item % 2 == 0 { count ; } } please help
31st Mar 2020, 3:58 AM
Hemant Kumar Sharma
Hemant Kumar Sharma - avatar
- 1
sem have you been through courses of java?
12th Dec 2016, 2:39 AM
Morpheus
Morpheus - avatar
- 5
ah shet
7th Jan 2017, 6:14 AM
Benyamin Dolat Dost
Benyamin Dolat Dost - avatar