枚举中间可能出现的天气
1 #include<stdio.h> 2 #include<string.h> 3 #include<stdlib.h> 4 const int maxn = 1005; 5 double mat[ 5 ][ 5 ]; 6 7 void solve( int L,int R,int n ){ 8 double ans[ 5 ],tp[ 5 ]; 9 double res = 0; 10 for( int i=1;i<=n;i++ ){ 11 if( i==1 ){ 12 ans[ 1 ] = mat[ L ][ 1 ]; 13 ans[ 2 ] = mat[ L ][ 2 ]; 14 ans[ 3 ] = mat[ L ][ 3 ]; 15 //printf("i = 1: %lf %lf %lf ",ans[1],ans[2],ans[3]); 16 continue; 17 } 18 else if( i==n ){ 19 res = ans[ 1 ]*mat[ 1 ][ R ]; 20 res += ans[ 2 ]*mat[ 2 ][ R ]; 21 res += ans[ 3 ]*mat[ 3 ][ R ]; 22 continue; 23 } 24 else { 25 tp[1] = ans[1],tp[2] = ans[2],tp[3] = ans[3]; 26 ans[ 1 ] = tp[ 1 ]*mat[ 1 ][ 1 ]+tp[ 2 ]*mat[ 2 ][ 1 ]+tp[ 3 ]*mat[ 3 ][ 1 ]; 27 ans[ 2 ] = tp[ 1 ]*mat[ 1 ][ 2 ]+tp[ 2 ]*mat[ 2 ][ 2 ]+tp[ 3 ]*mat[ 3 ][ 2 ]; 28 ans[ 3 ] = tp[ 1 ]*mat[ 1 ][ 3 ]+tp[ 2 ]*mat[ 2 ][ 3 ]+tp[ 3 ]*mat[ 3 ][ 3 ]; 29 // ans[1] = tp[1],ans[2] = tp[2],ans[3] = tp[3]; 30 //printf("i = %d: %lf %lf %lf ",i,ans[1],ans[2],ans[3]); 31 continue; 32 } 33 } 34 printf("%.3lf ",res); 35 } 36 37 int main(){ 38 //freopen("in.txt","r",stdin); 39 int T; 40 scanf("%d",&T); 41 while( T-- ){ 42 for( int i=1;i<=3;i++ ){ 43 for( int j=1;j<=3;j++ ){ 44 scanf("%lf",&mat[ i ][ j ]); 45 } 46 } 47 int K; 48 scanf("%d",&K); 49 while( K-- ){ 50 int L,R,N; 51 scanf("%d%d%d",&L,&R,&N); 52 if( N==1 ){ 53 printf("%.3lf ",mat[ L ][ R ]); 54 continue; 55 } 56 solve( L,R,N ); 57 } 58 } 59 return 0; 60 }