Ari*_*lam 0 java methods mergesort overriding
好的。我有一个标准的归并排序类。
public class Merge extends SortAlgorithm {
public static void sort(Comparable[] a) {
Comparable[] aux = new Comparable[a.length];
sort(a, aux, 0, a.length -1);
}
protected static void sort(Comparable[] a, Comparable[] aux, int lo, int hi) {
if(hi <= lo)
return;
int mid = (lo + hi)/2;
sort(a, aux, lo, mid);
sort(a, aux, mid+1, hi);
if(less(a[mid+1], a[mid]))
merge(a, aux, lo, mid, hi);
}
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String[] a = br.readLine().split(" ");
sort(a);
show(a);
}
protected static void merge(Comparable[] a, Comparable[] aux, int lo, int mid, int hi) {
int i = lo , j = mid+1;
for(int k = lo ; k <= hi ; k++)
aux[k] = a[k];
for( int k = lo ; k <= hi ; k++ ) {
if(i > mid) //Boundary Conditions
a[k] = aux[j++]; //
else if(j > hi) //
a[k] = aux[i++]; //
else if(less(aux[i] , aux[j]))
a[k] = aux[i++];
else
a[k] = aux[j++];
}
}
}
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我扩展了这个类来创建一个更新版本的合并排序,它使用较少的辅助数组。它有一个不同的“合并”和“排序(比较[])”功能
public class MergeSmallerAuxArray extends Merge {
public static void sort(Comparable[] a) {
Comparable[] aux = new Comparable[a.length/2];
sort(a, aux, 0, a.length - 1);
}
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String[] a = br.readLine().split(" ");
sort(a);
show(a);
}
//method overidden below
public static void merge(Comparable[] a, Comparable[] aux, int lo, int mid, int hi) { int i = lo , j = mid+1;
for(int k = lo ; k <= mid ; k++)
aux[k] = a[k];
for(int k = lo ; k <= hi ; k++) {
if(i > mid)
a[k] = a[j++];
else if(j > hi)
a[k] = aux[i++];
else if(less(aux[i], a[j]))
a[k] = aux[i++];
else
a[k] = a[j++];
}
}
}
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但是每次我运行这个类时,我都会收到一个错误,因为sort(Comparable[],Comparable[],int,int)超类的方法正在调用超类的合并函数,而不是我覆盖的函数。我哪里出错了?请帮忙。谢谢你。