HDU1437+模拟

枚举中间可能出现的天气

 #include<stdio.h>
 #include<string.h>
 #include<stdlib.h>
 const int maxn = ;
 double mat[  ][  ];

 void solve( int L,int R,int n ){
     double ans[  ],tp[  ];
     double res = ;
     for( int i=;i<=n;i++ ){
         if( i== ){
             ans[  ] = mat[ L ][  ];
             ans[  ] = mat[ L ][  ];
             ans[  ] = mat[ L ][  ];
             //printf("i = 1: %lf %lf %lf\n",ans[1],ans[2],ans[3]);
             continue;
         }
         else if( i==n ){
             res = ans[  ]*mat[  ][ R ];
             res += ans[  ]*mat[  ][ R ];
             res += ans[  ]*mat[  ][ R ];
             continue;
         }
         else {
             tp[] = ans[],tp[] = ans[],tp[] = ans[];
             ans[  ] = tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ];
             ans[  ] = tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ];
             ans[  ] = tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ]+tp[  ]*mat[  ][  ];
            // ans[1] = tp[1],ans[2] = tp[2],ans[3] = tp[3];
             //printf("i = %d: %lf %lf %lf\n",i,ans[1],ans[2],ans[3]);
             continue;
         }
     }
     printf("%.3lf\n",res);
 }

 int main(){
     //freopen("in.txt","r",stdin);
     int T;
     scanf("%d",&T);
     while( T-- ){
         for( int i=;i<=;i++ ){
             for( int j=;j<=;j++ ){
                 scanf("%lf",&mat[ i ][ j ]);
             }
         }
         int K;
         scanf("%d",&K);
         while( K-- ){
             int L,R,N;
             scanf("%d%d%d",&L,&R,&N);
             if( N== ){
                 printf("%.3lf\n",mat[ L ][ R ]);
                 continue;
             }
             solve( L,R,N );
         }
     }
     return ;
 }