微软等数据结构+算法面试100题005

#include <iostream>

void downHeap(int heapArray[], int lengtArray, int key)

{

int temp = key;

int flag = 0;

int maxkey ;

while ( temp <= (lengtArray-2) / 2 ) {

if ( temp*2 + 2 <= lengtArray -1 ) {//最后一个节点有右儿子

maxkey = ( heapArray[temp*2+1] < heapArray[temp*2+2] ) ? (temp*2+2) : (temp*2+1) ;

}

else {

maxkey = temp*2 + 1;

}

if ( heapArray[temp] < heapArray[maxkey]) {

flag = heapArray[temp];

heapArray[temp] = heapArray[maxkey];

heapArray[maxkey] = flag ;

temp = maxkey ; //继续向下搜索

}

else

return ;

}

}

void buildMaxHeap(int heapArray[], int lengthArray)

{

for (int i = (lengthArray - 2) / 2 ; i >= 0; i --) {

downHeap(heapArray, lengthArray, i);

}

}

int mindata(int heapArray[])

{

return heapArray[0];

}

void Printheap(int heapArray[], int length)

{

int i = length - 1;

int temp;

while( i > 1 ) {

temp = heapArray[i];

heapArray[i] = heapArray[0];

heapArray[0] = temp;

if ( i > 2) { // 因为是downHeap是为了建最大堆，当只有两个数时，则经过一次转换已经是排好序了，不需要了。

downHeap(heapArray, i, 0);

}

i--;

}

i = 0;

while(i < length ){

std::cout<<heapArray[i]<<" ";

i++;

}

std::cout<<std::endl;

}

void findtheleast(int number, int data[], int length, int heapArray[])

{

for(int i = 0; i < number; i++ ) {

heapArray[i] = data[i];

}

buildMaxHeap(heapArray, number);

for(int i = number; i < length; i++) {

if ( data[i] < mindata(heapArray) ) {

heapArray[0] = data[i];

downHeap(heapArray, number, 0);

/* for (int i = 0; i< 4; i++){

std::cout<<heapArray[i]<<" ";

}

std::cout<<std::endl;*/

}

}

Printheap(heapArray, number);

}

int main()

{

int data[] ={8,7,6,5,4,3,2,1};

int heapArray[4] ={0};

findtheleast(4, data, sizeof(data)/sizeof(int), heapArray);

return 0;

}

#include <iostream>

void downHeap(int heapArray[], int lengtArray, int key)

{

int temp = key;

int flag = 0;

int maxkey ;

while ( temp <= (lengtArray-2) / 2 ) {

if ( temp*2 + 2 <= lengtArray -1 ) {//最后一个节点有右儿子

maxkey = ( heapArray[temp*2+1] < heapArray[temp*2+2] ) ? (temp*2+2) : (temp*2+1) ;

}

else {

maxkey = temp*2 + 1;

}

if ( heapArray[temp] < heapArray[maxkey]) {

flag = heapArray[temp];

heapArray[temp] = heapArray[maxkey];

heapArray[maxkey] = flag ;

temp = maxkey ; //继续向下搜索

}

else

return ;

}

}

void buildMaxHeap(int heapArray[], int lengthArray)

{

for (int i = (lengthArray - 2) / 2 ; i >= 0; i --) {

downHeap(heapArray, lengthArray, i);

}

}

int mindata(int heapArray[])

{

return heapArray[0];

}

void Printheap(int heapArray[], int length)

{

int i = length - 1;

int temp;

while( i > 1 ) {

temp = heapArray[i];

heapArray[i] = heapArray[0];

heapArray[0] = temp;

if ( i > 2) { // 因为是downHeap是为了建最大堆，当只有两个数时，则经过一次转换已经是排好序了，不需要了。

downHeap(heapArray, i, 0);

}

i--;

}

i = 0;

while(i < length ){

std::cout<<heapArray[i]<<" ";

i++;

}

std::cout<<std::endl;

}

void findtheleast(int number, int data[], int length, int heapArray[])

{

for(int i = 0; i < number; i++ ) {

heapArray[i] = data[i];

}

buildMaxHeap(heapArray, number);

for(int i = number; i < length; i++) {

if ( data[i] < mindata(heapArray) ) {

heapArray[0] = data[i];

downHeap(heapArray, number, 0);

/* for (int i = 0; i< 4; i++){

std::cout<<heapArray[i]<<" ";

}

std::cout<<std::endl;*/

}

}

Printheap(heapArray, number);

}

int main()

{

int data[] ={8,7,6,5,4,3,2,1};

int heapArray[4] ={0};

findtheleast(4, data, sizeof(data)/sizeof(int), heapArray);

return 0;

}#include <iostream>

void downHeap(int heapArray[], int lengtArray, int key)

{

int temp = key;

int flag = 0;

int maxkey ;

while ( temp <= (lengtArray-2) / 2 ) {

if ( temp*2 + 2 <= lengtArray -1 ) {//最后一个节点有右儿子

maxkey = ( heapArray[temp*2+1] < heapArray[temp*2+2] ) ? (temp*2+2) : (temp*2+1) ;

}

else {

maxkey = temp*2 + 1;

}

if ( heapArray[temp] < heapArray[maxkey]) {

flag = heapArray[temp];

heapArray[temp] = heapArray[maxkey];

heapArray[maxkey] = flag ;

temp = maxkey ; //继续向下搜索

}

else

return ;

}

}

void buildMaxHeap(int heapArray[], int lengthArray)

{

for (int i = (lengthArray - 2) / 2 ; i >= 0; i --) {

downHeap(heapArray, lengthArray, i);

}

}

int mindata(int heapArray[])

{

return heapArray[0];

}

void Printheap(int heapArray[], int length)

{

int i = length - 1;

int temp;

while( i > 1 ) {

temp = heapArray[i];

heapArray[i] = heapArray[0];

heapArray[0] = temp;

if ( i > 2) { // 因为是downHeap是为了建最大堆，当只有两个数时，则经过一次转换已经是排好序了，不需要了。

downHeap(heapArray, i, 0);

}

i--;

}

i = 0;

while(i < length ){

std::cout<<heapArray[i]<<" ";

i++;

}

std::cout<<std::endl;

}

void findtheleast(int number, int data[], int length, int heapArray[])

{

for(int i = 0; i < number; i++ ) {

heapArray[i] = data[i];

}

buildMaxHeap(heapArray, number);

for(int i = number; i < length; i++) {

if ( data[i] < mindata(heapArray) ) {

heapArray[0] = data[i];

downHeap(heapArray, number, 0);

/* for (int i = 0; i< 4; i++){

std::cout<<heapArray[i]<<" ";

}

std::cout<<std::endl;*/

}

}

Printheap(heapArray, number);

}

int main()

{

int data[] ={8,7,6,5,4,3,2,1};

int heapArray[4] ={0};

findtheleast(4, data, sizeof(data)/sizeof(int), heapArray);

return 0;

}

基本的思路是：通过一个4个单元的数组，记录当前的最小的4个数 通过堆排序。 最后将这四个数输出。