4368: [IOI2015]boxes纪念品盒

4368: [IOI2015]boxes纪念品盒

链接

分析
　　链接

代码

 #include<bits/stdc++.h>
 using namespace std;
 typedef long long LL;

 inline int read() {
     int x=,f=;char ch=getchar();for(;!isdigit(ch);ch=getchar())if(ch=='-')f=-;
     for (;isdigit(ch);ch=getchar())x=x*+ch-'';return x*f;
 }

 const int N = 1e7+;
 int s1[N],s2[N],p1,p2;
 LL f1[N],f2[N]; //-

 int main() {
     int n = read(),k = read(),L = read();
     for (int i=; i<=n; ++i) {
         int x = read();
         if (x <= L/) s1[++p1] = x;
         else s2[++p2] = L - x;
     }
     for (int i=,lim=p2/; i<=lim; ++i) swap(s2[i],s2[p2-i+]);
     for (int i=; i<=p1; ++i) {
         if (i <= k) f1[i] = s1[i];
         else f1[i] = f1[i-k] + s1[i];
     }
     for (int i=; i<=p2; ++i) {
         if (i <= k) f2[i] = s2[i];
         else f2[i] = f2[i-k] + s2[i];
     }
     LL ans =  * (f1[p1] + f2[p2]);
     for (int i=p1-k; i<=p1; ++i) {
         ans = min(ans,*(f1[i]+f2[max(p2-k+p1-i,)])+L);
     }
     cout << ans;
     return ;
 }