2763: [JLOI2011]飞行路线

裸的狄杰，但我不太会写堆，抄了很久。

#include<cstdio>#include<iostream>#include<cstring>#include<algorithm>#include<vector>#include<queue>#include<cmath>#include<map>#include<bitset>using namespace std;#define rep(i,j,k) for(i=j;i<=k;++i)#define per(i,j,k) for(i=j;i>=k;--i)#define sqr(x) ((x)*(x))#define G getchar()#define LL long long#define pii pair<int,int>#define mkp make_pair#define X first#define Y second#define N 10005#define NN 50005#define inf 1061109567int n,m,k,st,en,ans;int he[N],ne[NN<<1],to[NN<<1],W[NN<<1],tot;int d[N][11],Hp[N*11],sopx[N*11],sopy[N*11],pos[N][11],id;LL read(){LL x=0;char ch=G;bool flg=0;while((ch<48||ch>57)&&ch!=45)ch=G;if(ch==45)flg=1,ch=G;for(;ch>47&&ch<58;ch=G)x=x*10+ch-48;return flg?-x:x;}void add(int x,int y,int z){to[++tot]=y;W[tot]=z;ne[tot]=he[x];he[x]=tot;}void Swap(int x,int y){swap(pos[sopx[x]][sopy[x]],pos[sopx[y]][sopy[y]]);swap(sopx[x],sopx[y]);swap(sopy[x],sopy[y]);swap(Hp[x],Hp[y]);}void ins(int x,int y){Hp[++id]=d[x][y];pos[sopx[id]=x][sopy[id]=y]=id;for(x=id;Hp[x]<Hp[x>>1];x>>=1)Swap(x,x>>1);}void del(int x){int y;Swap(x,id--);for(y=x;y>1&&Hp[y]<Hp[y>>1];y>>=1)Swap(y,y>>1);while(1){y=x<<1;if(y>id)break;if(y<id&&Hp[y]>Hp[y|1])y|=1;if(Hp[y]>=Hp[x])break;Swap(x,y);x=y;}}void up(int x,int y,int z){if(z<d[x][y]){if(d[x][y]<inf)del(pos[x][y]);d[x][y]=z;ins(x,y);}}int main(){int i,x,y,z;n=read();m=read();k=read();st=read()+1;en=read()+1; for(tot=1;m--;){x=read()+1;y=read()+1;z=read();add(x,y,z);add(y,x,z);}memset(d,63,sizeof d);d[st][0]=0;ins(st,0);while(id){x=sopx[1];y=sopy[1];del(1);for(i=he[x];i;i=ne[i]){up(to[i],y,d[x][y]+W[i]);if(y<k)up(to[i],y+1,d[x][y]);}} ans=d[en][0];rep(i,1,k)ans=min(ans,d[en][i]);printf("%d\n",ans);return 0;}