Submission #7651

#	Time	Username	Problem	Language	Result	Execution time	Memory
7651		imsifile	Split the sequence (APIO14_sequence)	C++98	0 / 100	0 ms	131072 KiB

sequence

#include<stdio.h>
#define sq(a) ((a)*(a))
#define sik(l,x) ((l.a)*(x)+(l.b))

typedef long long lld;

struct lin {
	int ix;
	lld a, b; // ax+b
}stk[100100], im;

int n, k, di[100100][202], scn;
lld ba[100100], dy[100100][202], sum[100100];

int main(){
	int i, i2, j, t=1;
	scanf("%d%d", &n, &k);
	for(i=1; i<=n; i++)scanf("%lld", &ba[i]), sum[i]=sum[i-1]+ba[i];
	for(i=1; i<=n; i++)dy[i][0]=sq(sum[i]);
	for(j=1; j<=k; j++){
		im.a=-2*sum[j], im.b=dy[j][j-1]+sq(sum[j]), im.ix=j;
		stk[0]=im, scn=1;
		for(i=1; i<=j; i++)dy[i][t]=0;
		for(i=j+1, i2=0; i<=n; i++){
			for(; i2<scn-1; i2++){
				if(sik(stk[i2],sum[i])<sik(stk[i2+1],sum[i]))break;
			}
			di[i][j]=stk[i2].ix, dy[i][j]=sq(sum[i])+sik(stk[i2],sum[i]);
			im.ix=i, im.a=-2*sum[i], im.b=dy[i][j-1]+sq(sum[i]);
			for(; scn; scn--){
				if(stk[scn-1].b<im.b)break;
			}
			stk[scn++]=im;
			if(i2>=scn)i2=scn-1;
		}
		t=1-t;
	}
	printf("%lld\n", (sq(sum[n])-dy[n][k])/2);
	for(i=n, j=k; j>0; j--)printf("%d ", di[i][j]), i=di[i][j];
	return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 11
• Subtask 3: 0 / 11
• Subtask 4: 0 / 17
• Subtask 5: 0 / 21
• Subtask 6: 0 / 29