Algorithm note-The shortest-path algorithm

1. Single Source shortest circuit problem

①dijkstra algorithm:

Normal version:

#defineMem (b) memset ((a), (b), sizeof (a))Const intinf=0x3f3f3f3f;Const intn= the;intG[n][n];intD[n];BOOLVis[n];intn,m;voidDijkstra (ints)    {mem (D,inf); Mem (Vis,false); D[s]=0;  while(true)    {        intv=-1;  for(intI=1; i<=n;i++)        if(!vis[i]&& (v==-1|| D[I]&LT;D[V]) v=i; if(v==-1) Break; VIS[V]=true;  for(intI=1; i<=n;i++) {D[i]=min (d[i],d[v]+G[v][i]); }    }}

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Example: hdu2544 shortest circuit

Code:

#include <bits/stdc++.h>using namespacestd;#definell Long Long#defineLS rt<<1,l,m#defineRS Rt<<1|1,m+1,r#definePB Push_back#defineMem (b) memset ((a), (b), sizeof (a))Const intinf=0x3f3f3f3f;Const intn= the;intG[n][n];intD[n];BOOLVis[n];intn,m;voidDijkstra (ints)    {mem (D,inf); Mem (Vis,false); D[s]=0;  while(true)    {        intv=-1;  for(intI=1; i<=n;i++)        if(!vis[i]&& (v==-1|| D[I]&LT;D[V]) v=i; if(v==-1) Break; VIS[V]=true;  for(intI=1; i<=n;i++) {D[i]=min (d[i],d[v]+G[v][i]); }    }}intMain () { while(~SCANF ("%d%d", &n,&m) &&n&&m) {mem (g,inf);  for(intI=0; i<m;i++)        {            intA,b,c; CIN>>a>>b>>C; G[A][B]=B; G[b][a]=C; } Dijkstra (1); printf ("%d\n", D[n]); }    return 0;} 

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Not to be continued ...

Algorithm note-The shortest-path algorithm