Submission #403036

#	Time	Username	Problem	Language	Result	Execution time	Memory
403036		Waratpp123	Split the sequence (APIO14_sequence)	C++14	100 / 100	879 ms	81764 KiB

sequence

#include<bits/stdc++.h>
using namespace std;
long long a[100010],qs[100010],dp[2][100010];
int p[205][100010],n,k;
void play(int st,int l,int r,int optl,int optr){
    int mid=(l+r)/2,pos,i;
    long long mi=1e18;
    if(l>r) return;
    for(i=optl;i<=min(mid,optr);i++){
        if(dp[1-st%2][i-1]+(qs[mid]-qs[i-1])*(qs[mid]-qs[i-1])<=mi){
            mi=dp[1-st%2][i-1]+(qs[mid]-qs[i-1])*(qs[mid]-qs[i-1]);
            pos=i;
        }
    }
    dp[st%2][mid]=mi;
    p[st][mid]=pos-1;
    play(st,l,mid-1,optl,pos);
    play(st,mid+1,r,pos,optr);
}
int main(){
    int i,j,now;
    scanf("%d %d",&n,&k);
    for(i=1;i<=n;i++){
        scanf("%lld",&a[i]);
        qs[i]=qs[i-1]+a[i];
    }
    for(i=1;i<=n;i++){
        dp[0][i]=qs[i]*qs[i];
    }
    for(i=1;i<=k;i++){
        play(i,1,n,1,n);
    }
    printf("%lld\n",(qs[n]*qs[n]-dp[k%2][n])/2);
    now=n;
    for(i=k;i>=1;i--){
        printf("%d ",p[i][now]);
        now=p[i][now];
    }
return 0;
}
/*
7 3
4 1 3 4 0 2 3
*/

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:21:11: warning: unused variable 'j' [-Wunused-variable]
   21 |     int i,j,now;
      |           ^
sequence.cpp:22:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     scanf("%d %d",&n,&k);
      |     ~~~~~^~~~~~~~~~~~~~~
sequence.cpp:24:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |         scanf("%lld",&a[i]);
      |         ~~~~~^~~~~~~~~~~~~~
sequence.cpp: In function 'void play(int, int, int, int, int)':
sequence.cpp:16:19: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |     p[st][mid]=pos-1;
      |                ~~~^~

• Subtask 1: 11 / 11
• Subtask 2: 11 / 11
• Subtask 3: 11 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 29 / 29