+ 7

Help please!!! can someone explain why the output of this code is 26?

var a = [7,9,3,4]; for (var i = 1;i<4;i++){ a[0]+=a[i]+1; } alert(a[0]);

17th Jan 2018, 8:37 PM
HRMtech
HRMtech - avatar
2 ответов
+ 11
the loops runs 3 times, with i = 1, i = 2, i = 3. so it does: a[0] += a[1] + 1 a[0] += a[2] + 1 a[0] += a[3] + 1 and the values are: 7 += 9 + 1 //17 17 += 3 + 1 //21 21 += 4 + 1 //26 so after the code runs a[0] is 26
17th Jan 2018, 8:52 PM
wout werkman
wout werkman - avatar
+ 8
3 Iterations [7,9,3,4] 1st Iteration i=1 ● a[0] = 7 ■ a[0] = a[0]+a[1]+1 = 7 + 9 + 1 = 17 2 nd Iteration i=2 ● a[0] = 17 ■ a[0] = a[0]+a[2]+1 = 17 + 3 + 1 = 21 3 rd Iteration i=2 ● a[0] = 21 ■ a[0] = a[0]+a[2]+1 = 21 + 4 + 1 a[0] = 26
19th Jan 2018, 8:46 AM
I'm_Groot
I'm_Groot - avatar