Submission #116987

#	Time	Username	Problem	Language	Result	Execution time	Memory
116987		evpipis	Gap (APIO16_gap)	C++17	100 / 100	62 ms	2460 KiB

gap

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

#define pb push_back
typedef long long ll;

const int len = 1e5+5;
const ll maxi = 1e18;

//#define TEST

#ifndef TEST
#include "gap.h"
#endif // TEST

#ifdef TEST
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;

long long findGap(int, int);

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 = stdin, *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

long long findGap(int t, int n){
    ll ans = 0, l = 0, r = maxi, mn, mx;

    if (t == 1){
        vector<ll> vec;

        while (l <= r && vec.size() != n){
            MinMax(l, r, &mn, &mx);
            if (mn == mx){
                if (mn != -1)
                    vec.pb(mn);
                break;
            }

            l = mn+1, r = mx-1;
            vec.pb(mn), vec.pb(mx);
        }

        sort(vec.begin(), vec.end());

        for (int i = 0; i+1 < vec.size(); i++)
            ans = max(ans, vec[i+1]-vec[i]);
    }
    else{
        ll mi, mx; MinMax(0, maxi, &mi, &mx);
        ll L, R, len = mx - mi + 1;
        ll blok = len / n;
        ll lst = mi;
        ans = blok;
        for(ll i = mi + 1;i < mx;){
            MinMax(i, i + ans - 1, &L, &R); i += ans;
            if(L != -1){
                ans = max(ans, L - lst);
                lst = R;
            }
        }
        ans = max(ans, mx - lst);
        return ans;
        /*MinMax(l, r, &mn, &mx);

        ll low = (mx-mn)/(n-1), pre = mn, up = mx;

        //printf("mn = %lld, mx = %lld, l = %lld, r = %lld\n", mn, mx, l, r);

        l = mn+1;
        while (l <= up){
            MinMax(l, l+low-1, &mn, &mx);

            //printf("from %lld to %lld, mn = %lld, mx = %lld\n", l, l+low-1, mn, mx);

            if (mn != -1){
                ans = max(ans, mn-pre);
                pre = mx;
            }

            l += low;
        }*/
    }

    //printf("ans = %lld\n", ans);
    return ans;
}

Compilation message (stderr)

gap.cpp: In function 'long long int findGap(int, int)':
gap.cpp:69:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while (l <= r && vec.size() != n){
                          ~~~~~~~~~~~^~~~
gap.cpp:83:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i+1 < vec.size(); i++)
                         ~~~~^~~~~~~~~~~~

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