Submission #40724

#	Time	Username	Problem	Language	Result	Execution time	Memory
40724		bogdan10bos	Gap (APIO16_gap)	C++14	100 / 100	81 ms	2660 KiB

gap

#include <bits/stdc++.h>

//#define DEBUG
#include "gap.h"

using namespace std;

typedef long long LL;

long long findGap(int op, int N)
{
    if(op == 1)
    {
        LL st = 0, dr = 1e18;
        vector<LL> v;
        for(int i = 1; i <= N; i += 2)
        {
            LL vl, vr;
            MinMax(st, dr, &vl, &vr);
            v.push_back(vl);
            if(i + 1 <= N)  v.push_back(vr);
            st = vl + 1;
            dr = vr - 1;
        }
        sort(v.begin(), v.end());

        LL ans = 0;
        for(int i = 1; i < v.size(); i++)
            ans = max(ans, v[i] - v[i - 1]);
        return ans;
    }
    else if(op == 2)
    {
        LL st, dr;
        MinMax(0LL, LL(1e18), &st, &dr);
        LL ans = 0;
        LL lgt = ceil( (long double)(dr - st) / (long double)(N - 1) );

        LL rgt = st;
        for(LL lft = st; lft < dr; lft += lgt)
        {
            LL x, y;
            MinMax(lft, lft + lgt - 1, &x, &y);
            if(x == -1) continue;
            ans = max(ans, x - rgt);
            rgt = y;
        }
        ans = max(ans, dr - rgt);

        return ans;
    }
    return 0LL;
}


#ifdef DEBUG
#include <stdio.h>
#include <stdlib.h>

static void my_assert(int k){ if (!k) exit(1); }

static int subtask_num, N;
static long long A[100001];
static long long call_count;

void MinMax(long long s, long long t, long long *mn, long long *mx)
{
	int lo = 1, hi = N, left = N+1, right = 0;
	my_assert(s <= t && mn != NULL && mx != NULL);
	while (lo <= hi){
		int mid = (lo+hi)>>1;
		if (A[mid] >= s) hi = mid - 1, left = mid;
		else lo = mid + 1;
	}
	lo = 1, hi = N;
	while (lo <= hi){
		int mid = (lo+hi)>>1;
		if (A[mid] <= t) lo = mid + 1, right = mid;
		else hi = mid - 1;
	}
	if (left > right) *mn = *mx = -1;
	else{
		*mn = A[left];
		*mx = A[right];
	}
	if (subtask_num == 1) call_count++;
	else if (subtask_num == 2) call_count += right-left+2;
}

int main()
{
	FILE *in = fopen("1.in", "r"), *out = stdout;
	my_assert(2 == fscanf(in, "%d%d", &subtask_num, &N));
	my_assert(1 <= subtask_num && subtask_num <= 2);
	my_assert(2 <= N && N <= 100000);
	for (int i=1;i<=N;i++) my_assert(1 == fscanf(in, "%lld", A+i));
	for (int i=1;i<N;i++) my_assert(A[i] < A[i+1]);
	fprintf(out, "%lld\n", findGap(subtask_num, N));
	fprintf(out, "%lld\n", call_count);
}
#endif

Compilation message (stderr)

gap.cpp: In function 'long long int findGap(int, int)':
gap.cpp:28:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i = 1; i < v.size(); i++)
                          ^

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70