算法：优先级队列

 

优先级队列:

 

 1 #include <stdio.h> 2  3 int A[100]; 4 int heapsize; 5  6 void swap(int i, int j) { 7     int temp = A[i]; 8     A[i] = A[j]; 9     A[j] = temp;10 }11 12 void huifu(int i){13     int maxheap = i;14     int l = 2*i;15     int r = 2*i + 1;16     if(l <= heapsize && A[l] > A[maxheap])17         maxheap = l;18     if(r <= heapsize && A[r] > A[maxheap])19         maxheap = r;20     if(i != maxheap){21         swap(maxheap, i);22         huifu(maxheap);23     }24 }    25 26 27 void sort(){28     while(heapsize>1) {29         swap(heapsize, 1);30         --heapsize;31         huifu(1);32     }33 }34 35 void insert(int x){36     int i;37     A[++heapsize] = x;38     i = heapsize;39     while(i > 1 && A[i] > A[i/2]) {40         swap(i, i/2);41         i >>= 1;42     }43     /*44     while(A[heapsize] > i && i>=0){45         i/=2;46         swap(A[heapsize], A[i]);47     }*/48 }49 50 int  max(){51     return A[1];52 }53 54 int extract_max(){55     int tmp = A[1];56     A[1] = A[heapsize--];57     huifu(1);58     return tmp;59 }60 61 void build(){62     int i;63     for(i=heapsize/2; i>0 ;--i){64         huifu(i);65     }66 }67 68 int main(int argc, char const *argv[])69 {70     int n, i;71     scanf("%d", &n);72     heapsize = n;73     for(i=1;i<=n;++i){74         scanf("%d", &A[i]);75     }76     build();77     sort();78     // insert(24);79     // insert(20);80     // insert(100);81     for(i = 1; i <= n; i++)82         printf("%d\n", A[i]);83     return 0;84 }