水DP。。。说好的n<=10000，我开到15000才过。害我WA了一版，踏马是在坑了么= =
1 #include<bits/stdc++.h> 2 #define inc(i,l,r) for(i=l;i<=r;i++) 3 #define dec(i,l,r) for(i=l;i>=r;i--) 4 #define inf 1e9 5 #define ll long long 6 #define mem(a) memset(a,0,sizeof(a)) 7 #define NM 15000+5 8 using namespace std; 9 int read(){ 10 int x=0,f=1;char ch=getchar(); 11 while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();} 12 while(isdigit(ch))x=x*10+ch-'0',ch=getchar(); 13 return f*x; 14 } 15 int i,j,x,n,m,a[NM],b[NM],t,k,c[NM]; 16 int main(){ 17 n=read(); 18 dec(i,n,1)a[i]=read(); 19 a[0]=inf; 20 inc(i,1,n){ 21 inc(j,0,i-1) 22 if(a[j]>a[i])b[i]=max(b[i],b[j]+1); 23 } 24 m=read(); 25 inc(i,1,m){ 26 k=x=read();t=0; 27 dec(j,n,1) 28 if(b[j]>=x){ 29 c[x--]=a[j]; 30 t=j; 31 break; 32 } 33 if(t==0)printf("Impossible\n"); 34 else{ 35 dec(j,t-1,1) 36 if(b[j]>=x&&a[j]>a[t]){ 37 c[x--]=a[j]; 38 t=j; 39 } 40 dec(j,k,2)printf("%d ",c[j]); 41 printf("%d\n",c[1]); 42 } 43 } 44 return 0; 45 }
