这题是DP？这DP挺怪。。。反正我想不出。。。
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 mem(a) memset(a,0,sizeof(a)) 5 #define ll long long 6 #define inf 1e10 7 #define NM 100+5 8 #define nm 100000+5 9 using namespace std; 10 int read(){ 11 int x=0,f=1;char ch=getchar(); 12 while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();} 13 while(isdigit(ch))x=x*10+ch-'0',ch=getchar(); 14 return f*x; 15 } 16 int n,m,i,j,a[NM],b[NM]; 17 ll c[nm]; 18 int main(){ 19 freopen("humble.in","r",stdin); 20 freopen("humble.out","w",stdout); 21 n=read();m=read(); 22 inc(i,1,n)a[i]=read(),b[i]=1; 23 c[1]=1; 24 inc(i,2,m+1){ 25 c[i]=inf; 26 inc(j,1,n){ 27 while(c[b[j]]*a[j]<=c[i-1])b[j]++; 28 c[i]=min(c[i],c[b[j]]*a[j]); 29 } 30 } 31 printf("%d ",c[m+1]); 32 return 0; 33 }