Many beginners can not tell the difference between a copy and play an array of aliases, or difficult to detect, and often confused. Now we look at.
1, first look at the array copy the code a:
int N=a.length;
double[] b=new double[N];
for(int i=0;i<N;i++)
b[i]=a[i];
2, then look to the code array from the alias b:
int[] a=new int[N];
...
a[i]=1234;
...
int[] b=a;
...
b[i]=5678; //a[i]的值也会变成5678
3 to fully understand them
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For a, once the declaration creates an array, its size is fixed. The program can be obtained by a.length array a [] of length, but it is always the last element a [a.length-1]. Then the original values of the array elements one by one to the new array.
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For b, the array name represents the entire array ------ If we are given an array variable to another variable, then the two variables point to the same array.
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and so:
The key: a the double [] b = new double [N]; statement. It creates a new array.
