1098. Insertion or Heap Sort 解析

和前面的 1088一样的，不过这次是堆排序。

堆排的时候前面是个最大堆，取最大值后调整堆就好。

#include <iostream>
#include <algorithm>

#define MAX 110

using namespace std;

int origin[MAX], half[MAX];

int n;

bool IsInserSort() {
int p = 2;
while (p <= n && half[p-1] <= half[p]) {
p++;
}
int pos = p;
while (p <= n && half[p] == origin[p]) {
p++;
}

if (p == n + 1) {
sort(origin + 1, origin + pos + 1);
return true;
}
else
return false;

}

void AdjustHeap(int st, int ed) {
if (st < ed) {
int left = 2 * st;
int right = 2 * st + 1;

int pos;
if (left < ed && right < ed) {
if (half[left] > half[right])
pos = left;
else
pos = right;
}
else if (left < ed && right >= ed) {
pos = left;
}
else
return;

if (half[pos] > half[st]) {
swap(half[pos], half[st]);
AdjustHeap(pos, ed);
}
else return;

}
}

int main() {
cin >> n;

for (int i = 1; i <= n; i++) {
cin >> origin[i];
}
for (int i = 1; i <= n; i++) {
cin >> half[i];
}

if (IsInserSort()) {
cout << "Insertion Sort" << endl;
cout << origin[1];
for (int i = 2; i <= n; i++) {
cout << " " << origin[i];
}
cout << endl;
}
else {

cout << "Heap Sort" << endl;
int pre = n;
int NowMax[MAX];

int max = -1;
for (int i = 1; i <= n; i++) {
if (max < half[i])
max = half[i];
NowMax[i] = max;
}

for (int i = n; i > 0; i--) {
if (half[i] < NowMax[i]) {//找到排好和没排好的区分地方
int temp = half[i];
half[i] = half[1];
half[1] = temp;
//调整堆
AdjustHeap(1, i);

break;
}
pre = i;
}

cout << half[1];
for (int i = 2; i <= n; i++) {
cout << " " << half[i];
}
cout << endl;

}

return 0;
}