POJ3253 Fence Repair

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哈夫曼思想，优先队列解决

手打版

就把上一篇堆的代码做了点改动

/*poj  3253368K47MS*/#include<map>#include<set>#include<list>#include<queue>#include<stack>#include<ctime>#include<cmath>#include<string>#include<vector>#include<cstdio>#include<cstdlib>#include<cstring>#include<iostream>#include<algorithm>#define MAXN 30005#define MAX_INT 2147483647#define FA(x) (x>>1) #define LC(x) ((x<<1))#define RC(x) ((x<<1)|1)#define MID(x,y) ( (x + y) >> 1 )#define TIME_BEGIN double t1 = clock()#define TIME_END double t2 = clock();printf("\n%.2lfms\n",t2-t1)using namespace std;int size,top = 1;__int64 heap[MAXN];bool cmp(__int64 a,__int64 b){return a < b;}void up(int id){if(id == 1)return ;if(!cmp(heap[FA(id)] , heap[id])){swap(heap[FA(id)] , heap[id]);up(FA(id));}}void down(int id){if(RC(id) <= size){if(cmp(heap[LC(id)] , heap[RC(id)]) && cmp(heap[LC(id)] , heap[id])){swap(heap[LC(id)] , heap[id]);down(LC(id));}else if(!cmp(heap[LC(id)] , heap[RC(id)]) && cmp(heap[RC(id)] , heap[id])){swap(heap[RC(id)] , heap[id]);down(RC(id));}}else if(LC(id) <= size){if(cmp(heap[LC(id)] , heap[id])){swap(heap[LC(id)] , heap[id]);down(LC(id));}}}void insert(__int64 t){heap[++size] = t;up(size);}__int64 dele(){__int64 tmp = heap[top];if(RC(top) <= size){if(heap[LC(top)] < heap[RC(top)]){tmp += heap[LC(top)];heap[LC(top)] = heap[size--];down(LC(top));}else{tmp += heap[RC(top)];heap[RC(top)] = heap[size--];down(RC(top));}heap[top] = tmp;down(top);}else{size --;tmp += heap[LC(top)];}return tmp;}void print(int num){int k = 1,cnt = 0,kk = 0;while(num){num -= k;while(kk < k){cnt ++; kk ++;cout<<heap[cnt]<<" ";}kk = 0;cout<<endl;k = min(k<<1, num);}}int main(){__int64 sum = 0;freopen("./3253.in" , "r" , stdin);int n;cin>>n;if(n == 1){cout<<0<<endl;return 0;}while(n--){int t;scanf("%d",&t);insert(t);}while(size > 1){sum+= dele();}cout<<sum<<endl;return 0;}

STL偷懒版

/*poj 3253324K32MS*/#include<queue>#include<cstdio>using namespace std;priority_queue<int>myQueue;int main(){int n,t;__int64 ans = 0;scanf("%d",&n);for(int i = 1;i <= n;i ++){scanf("%d",&t);t = -t;myQueue.push(t);}while(myQueue.size() > 1){__int64 t1 = myQueue.top();myQueue.pop();__int64 t2 = myQueue.top();myQueue.pop();t1 += t2;ans += t1;myQueue.push(t1);}printf("%I64d\n",-ans);return 0;}

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