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| // Hacker Cup 2017 | |
| // Round 3 | |
| // Steadfast Snakes | |
| // Jacob Plachta | |
| using namespace std; | |
| template<typename T> T Abs(T x) { return(x<0 ? -x : x); } | |
| template<typename T> T Sqr(T x) { return(x*x); } | |
| const int INF = (int)1e9; | |
| const LD EPS = 1e-9; | |
| const LD PI = acos(-1.0); | |
| bool Read(int &x) | |
| { | |
| char c,r=0,n=0; | |
| x=0; | |
| for(;;) | |
| { | |
| c=getchar(); | |
| if ((c<0) && (!r)) | |
| return(0); | |
| if ((c=='-') && (!r)) | |
| n=1; | |
| else | |
| if ((c>='0') && (c<='9')) | |
| x=x*10+c-'0',r=1; | |
| else | |
| if (r) | |
| break; | |
| } | |
| if (n) | |
| x=-x; | |
| return(1); | |
| } | |
| int L[2]; | |
| LL BLT[2][2][LIM]; | |
| void Update(int a,int b,int i,int v) | |
| { | |
| for(i++;i<=L[a];i+=(i&-i)) | |
| BLT[a][b][i]+=v; | |
| } | |
| LL Query(int a,int b,int i) | |
| { | |
| LL v=0; | |
| for(i++;i>0;i-=(i&-i)) | |
| v+=BLT[a][b][i]; | |
| return(v); | |
| } | |
| int main() | |
| { | |
| // vars | |
| int T,t; | |
| int N,A,B,C; | |
| LL K; | |
| int i,j,c,v,ans; | |
| int r1,r2,m; | |
| LL s; | |
| static int H[LIM]; | |
| static int n1,n2,c1[LIM],c2[LIM],v1[LIM],v2[LIM],vc1[LIM],vc2[LIM]; | |
| // testcase loop | |
| Read(T); | |
| Fox1(t,T) | |
| { | |
| // input | |
| scanf("%d%lld",&N,&K); | |
| Read(v),Read(A),Read(B),Read(C); | |
| Fox(i,N) | |
| { | |
| H[i]=v; | |
| v=((LL)A*v+B)%C+1; | |
| } | |
| // check if there's a single dominating ladder | |
| j=0; | |
| Fox(i,N) | |
| if (H[i]>H[j]) | |
| j=i; | |
| Fox(i,N) | |
| if ((i!=j) && (H[i]>H[j]-K-abs(i-j))) | |
| break; | |
| if (i==N) | |
| { | |
| // special case - only shorten the dominating ladder | |
| ans=0; | |
| Fox(i,N) | |
| if (i!=j) | |
| Max(ans,H[j]-(int)K+H[i]+abs(i-j)); | |
| goto Done; | |
| } | |
| // compress diagonal coordinates | |
| n1=n2=0; | |
| Fox(i,N) | |
| { | |
| c1[n1++]=v1[i]=i-H[i]; | |
| c2[n2++]=v2[i]=-i-H[i]; | |
| } | |
| sort(c1,c1+n1); | |
| sort(c2,c2+n2); | |
| L[0]=n1=unique(c1,c1+n1)-c1; | |
| L[1]=n2=unique(c2,c2+n2)-c2; | |
| Fox(i,N) | |
| { | |
| vc1[i]=lower_bound(c1,c1+n1,v1[i])-c1; | |
| vc2[i]=lower_bound(c2,c2+n2,v2[i])-c2; | |
| } | |
| // init BLTs | |
| Fill(BLT,0); | |
| Fox(i,N) | |
| { | |
| Update(1,0,vc2[i],1); | |
| Update(1,1,vc2[i],v2[i]); | |
| } | |
| // try every possible pyramid center x-coordinate | |
| ans=2*INF+N; | |
| Fox(i,N) | |
| { | |
| // move ladder i from right to left BLT | |
| Update(0,0,vc1[i],1); | |
| Update(0,1,vc1[i],v1[i]); | |
| Update(1,0,vc2[i],-1); | |
| Update(1,1,vc2[i],-v2[i]); | |
| // centered on i | |
| r1=max(i+1,N-i),r2=INF+N; | |
| while (r2>=r1) | |
| { | |
| m=(r1+r2)>>1; | |
| // left | |
| v=i-m; | |
| c=lower_bound(c1,c1+n1,v)-c1-1; | |
| s=Query(0,0,c)*v-Query(0,1,c); | |
| // right | |
| v=-i-m; | |
| c=lower_bound(c2,c2+n2,v)-c2-1; | |
| s+=Query(1,0,c)*v-Query(1,1,c); | |
| if (s<=K) | |
| r2=m-1,Min(ans,2*m); | |
| else | |
| r1=m+1; | |
| } | |
| // centered on i+0.5 | |
| if (i==N-1) | |
| break; | |
| r1=max(i+1,N-i-1),r2=INF+N; | |
| while (r2>=r1) | |
| { | |
| m=(r1+r2)>>1; | |
| // left | |
| v=i-m; | |
| c=lower_bound(c1,c1+n1,v)-c1-1; | |
| s=Query(0,0,c)*v-Query(0,1,c); | |
| // right | |
| v=-(i+1)-m; | |
| c=lower_bound(c2,c2+n2,v)-c2-1; | |
| s+=Query(1,0,c)*v-Query(1,1,c); | |
| if (s<=K) | |
| r2=m-1,Min(ans,2*m+1); | |
| else | |
| r1=m+1; | |
| } | |
| } | |
| Done:; | |
| printf("Case #%d: %d\n",t,ans); | |
| } | |
| return(0); | |
| } | |