Fzu 2173 Nostop

Test instructions

There are n cities, numbered 1~ you, M-Road, each road starting point is U, the end point is V, and the toll from U to V is cost, starting from 1, to get the minimum spend at k time to reach N, if the k time is unreachable n, then output-1

Method: flody+ Matrix Fast Power

Note: After the array invokes the function, its value will change (the function call of the array actually passes the position)

(Detailed http://blog.chinaunix.net/uid-16875687-id-2155704.html)

1#include <stdio.h>2 3 intFintb[2][2])4 {5      for(intI=0;i<2; i++)6     {7          for(intj=0;j<2; j + +)8b[i][j]++;9     }Ten } One intMain () A { -     inta[2][2]; -      for(intI=0;i<2; i++) the     { -          for(intj=0;j<2; j + +) -scanf"%d",&a[i][j]); -     } + f (a); -      for(intI=0;i<2; i++) +     { A          for(intj=0;j<2; j + +) atprintf"%d", A[i][j]); -     } -     return 0; -}

This problem can be understood as a K-Flody cycle (a city can be repeated), K value is too large, with the matrix to reduce the time of a fast power

1#include <iostream>2#include <algorithm>3 using namespacestd;4 #defineINF 1000000000000000LL//define default is int, the value is too large when plus ll5 #defineN 556 __int64 Ma[n][n],temp[n][n];7 intN;8 voidFloy (__int64 a[n][n])9 {Ten     inti,j,k; One      for(i=1; i<=n;i++) A          for(j=1; j<=n;j++) -TEMP[I][J] =INF; -      for(k=1; k<=n;k++) the          for(i=1; i<=n;i++) -              for(j=1; j<=n;j++) -Temp[i][j] = min (temp[i][j],a[i][k]+ma[k][j]); -      for(i=1; i<=n;i++) +          for(j=1; j<=n;j++) -A[I][J] =Temp[i][j];  + } A  at voidFintK,__int64 Dis[n][n]) - { -k--; -      while(k) -     { -         if(k&1) Floy (DIS);//Judging the odd and even odd &1=1 even &1=0 in Floy (MA); -k=k/2; to     } + } -  the intMain () * { $     intt,m,k;Panax Notoginseng     inti,j; -     intu,v; the __int64 cost; + __int64 Dis[n][n]; ACin>>T; the      while(t--) +     { -Cin>>n>>m>>K; $          for(i=1; i<=n;i++) $              for(j=1; j<=n;j++) -             { -dis[i][j]=INF; thema[i][j]=INF; -             }Wuyi              the          for(i=1; i<=m;i++) -         { WuCin>>u>>v>>Cost ; -             if(Ma[u][v]>cost)//Heavy Edge About             { $ma[u][v]=Cost ; -dis[u][v]=Ma[u][v]; -             } -         } A          + f (k,dis); the          -         if(dis[1][n]>=inf) cout<<"-1"<<Endl; $         Elsecout<<dis[1][n]<<Endl; the     } the     return 0; the}

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Fzu 2173 Nostop