Submission #45743

#	Time	Username	Problem	Language	Result	Execution time	Memory
45743		JohnTitor	Split the sequence (APIO14_sequence)	C++11	100 / 100	833 ms	82644 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
#define FOR(i, j, k) for(int i=(j); i<=(k); i++)
#define FFOR(i, j, k) for(int i=(j); i<(k); i++)
#define DFOR(i, j, k) for(int i=(j); i>=(k); i--)
#define bug(x) cerr<<#x<<" = "<<(x)<<'\n'
#define pb push_back
#define mp make_pair
#define setbit(s, i) (s|=(1LL<<(i)))
#define bit(s, i) (((s)>>(i))&1LL)
#define mask(i) ((1LL<<(i)))
#define builtin_popcount __builtin_popcountll
typedef long long ll;
typedef long double ld;
template <typename T> inline void read(T &x){
    char c;
    bool nega=0;
    while((!isdigit(c=getchar()))&&(c!='-'));
    if(c=='-'){
        nega=1;
        c=getchar();
    }
    x=c-48;
    while(isdigit(c=getchar())) x=x*10+c-48;
    if(nega) x=-x;
}
template <typename T> inline void writep(T x){
    if(x>9) writep(x/10);
    putchar(x%10+48);
}
template <typename T> inline void write(T x){
    if(x<0){
        putchar('-');
        x=-x;
    }
    writep(x);
}
template <typename T> inline void writeln(T x){
    write(x);
    putchar('\n');
}
#define taskname "sequence"
#define sqr(x) ((x)*(x))
int n, k;
int s[100001];
ll sqs[100001];
ll f[100001];
int trace[201][100001];
vector <int> q;
const ll inf=mask(60);
void track(int nn, int k){
    if(nn==0) return;
    track(trace[k][nn], k-1);
    if(nn==n) return;
    write(nn);
    putchar(' ');
}
int first[100001];
ll b[100001];
ll first_better(int i, int j){
    if(b[j]<=b[i]) return 0;
    if(s[i]==s[j]) return inf;
    return (b[j]-b[i]-1)/(s[i]-s[j])+1;
}
int main(){
    #ifdef Kanikou
        if(fopen(taskname".inp", "r"))
            freopen(taskname".inp", "r", stdin);
    #endif // Kanikou
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    read(n);
    read(k);
    FOR(i, 1, n) read(s[i]);
    FOR(i, 1, n) s[i]+=s[i-1];
    FOR(i, 1, n) sqs[i]=((ll)s[i])*s[i];
    ll a;
    FOR(j, 1, k){
        int p=0;
        q.clear();
        q.pb(0);
        FOR(i, 1, n){
            b[i]=f[i]-sqs[i];
            p=min(p, ((int)q.size())-1);
            while((p+1<q.size())&&(first[q[p+1]]<=s[i])) p++;
            f[i]=((ll)s[i])*s[q[p]]+b[q[p]];
            trace[j][i]=q[p];
            while(true){
                a=first_better(i, q.back());
                if(a>=s[n]) break;
                if(a<=first[q.back()]){
                    q.pop_back();
                    if(q.empty()){
                        first[i]=0;
                        q.pb(i);
                        break;
                    }
                }
                else{
                    first[i]=a;
                    q.pb(i);
                    break;
                }
            }
        }
    }
    writeln(f[n]);
    track(n, k);
}

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:85:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while((p+1<q.size())&&(first[q[p+1]]<=s[i])) p++;
                    ~~~^~~~~~~~~

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