java - Array in Array, what should be tracing of this code? -

java - Array in Array, what should be tracing of this code? -

int[] ar=new int[5]; int[] numoccurence = new int[ar.length]; (int = 0; < ar.length; i++){ ++numoccurence[ar[i]]; system.out.println(numoccurence[ar[i]]); }

first of there no array in array.

-if mean line,

int[] numoccurence = new int[ar.length];

then nil passing length of ar[] create new array

-if mean line, ++numoccurence[ar[i]]; or numoccurence[ar[i]]. 1 time again incrementing values in numoccurence[] , providing index of values based on values in arr[] , (arr[i] returns int)

an array of array this:-

integer[] array1 = new integer[]; integer[] array2 = new integer[]; integer[][] arrays = { array1, array2};

here arrays holds references arrays, integer reference arrays.

and said in comments code nil print 1,2,3,4,5.

and asked how code works, since not assigning values in array ar or numoccurence , values in them initialized 0. , hence in each iteration of loop this

++numoccurence[ar[i]]; system.out.println( numoccurence[ar[i]]);

now since values in ar 0 in code,ar[i] @ index homecoming 0. code can replaced this

++numoccurence[0]; system.out.println(numoccurence[0]);

and since incrementing same element ++numoccurence[0]; on each iteration print incrementing values 0+1,0+1+1,.... 5 .

java arrays