Submission #713658

# Submission time Handle Problem Language Result Execution time Memory
713658 2023-03-22T18:58:54 Z mtxas Potatoes and fertilizers (LMIO19_bulves) C++14
24 / 100
85 ms 13164 KB
#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#define int long long
#define DISABLE_PRINTF
#ifdef DISABLE_PRINTF
#define printf(...)
#endif // DISABLE_PRINTF
using namespace std;
void solve()
{
    int n;
    cin >> n;
    vector<int> a(n + 1), b(n + 1);
    for(int i = 1; i <= n; ++i)
    {
        cin >> a[i] >> b[i];
    }
    int A = 0;
    int B = 0;
    for(int i = 1; i <= n; ++i)
    {
        A += a[i], B += b[i];
    }
    if(A == B)
    {
        /// solve it
        int ans = 0;
        int aid = 1, bid = 1;
        for(; bid <= n; ++bid)
        {
            for(; b[bid] > 0; ++aid)
            {
                int take = min(a[aid], b[bid]);
                b[bid] -= take;
                a[aid] -= take;
                ans += take * abs(bid - aid);
                if(b[bid] == 0)
                {
                    break;
                }
            }
        }
        cout << ans;
    }
    else if(A == B + 1)
    {
        vector<int> pref(n + 1), suff(n + 2);
        vector<int> prefLast(n + 1), suffLast(n + 2);
        vector<int> bcopy = b;
        vector<int> acopy = a;
        /// calc the pref
        int aid = 1;
        for(int i = 1; i <= n; ++i)
        {
            pref[i] = pref[i - 1];
            for(; b[i] > 0; aid += (a[aid] == 0))
            {
                int take = min(a[aid], b[i]);
                b[i] -= take;
                a[aid] -= take;
                pref[i] += abs(i - aid) * take;
                if(take == 0) continue;
                prefLast[i] = aid;
            }
        }
        a = acopy;
        b = bcopy;
        /// calc the suff
        aid = n;
        for(int i = n; i >= 1; --i)
        {
            suff[i] = suff[i + 1];
            for(; b[i] > 0; aid -= (a[aid] == 0))
            {
                int take = min(a[aid], b[i]);
                b[i] -= take;
                a[aid] -= take;
                suff[i] += abs(aid - i) * take;
                if(take == 0) continue;
                suffLast[i] = aid;
            }
        }
        a = acopy;
        b = bcopy;
        /// calc ferPref and ferSuff
        vector<int> ferPref(n + 1), ferSuff(n + 2);
        vector<int> potPref(n + 1), potSuff(n + 2);
        for(int i = 1; i <= n; ++i)
        {
            ferPref[i] = ferPref[i - 1] + a[i];
            ferSuff[n + 1 - i] = ferSuff[n + 1 - i + 1] + a[n + 1 - i];
            potPref[i] = potPref[i - 1] + b[i];
            potSuff[n + 1 - i] = potSuff[n + 1 - i + 1] + b[n + 1 - i];
        }
        /// calc the answer
        int ans = min(pref[n], suff[1]);
        vector<int> potIds;
        for(int i = 1; i <= n; ++i)
        {
            if(b[i] > 0)
            {
                potIds.push_back(i);
            }
        }
        printf("|potIds| = %d\n", (int) potIds.size());
        for(int j = 0; j < potIds.size() - 1; ++j)
        {
            int l = potIds[j];
            int r = potIds[j + 1];
            int initAns = pref[l] + suff[r];
            int curAns = initAns;
            /// find the location of fertilizer
            int fl = prefLast[l];
            int fr = suffLast[r];
            int flSum = ferPref[fl];
            int frSum = ferSuff[fr];
            int blSum = potPref[l];
            int brSum = potSuff[r];
            printf("(l, r) = (%d, %d)\n(fl, fr) = (%d, %d)\n(flSum, frSum) = (%d, %d)\n(blSum, brSum) = (%d, %d)\n", l, r, fl, fr, flSum, frSum, blSum, brSum);
            if(fl == fr) continue;
            assert(blSum + brSum == potPref[n]);
            assert(flSum + frSum == ferPref[n] - 1 || flSum + frSum == ferPref[n]);
            if(flSum == blSum && frSum == brSum)
            {
                for(int q = fl + 1; q < fr; ++q)
                {
                    if(a[q] > 0)
                    {
                        curAns = min({curAns,
                                      initAns + abs(l - q) - abs(fl - q),
                                      initAns + abs(r - q) - abs(fr - q)});
                        break;
                    }
                    assert(q != fr - 1);
                }
            }
            else if(flSum < blSum )
            {
                curAns = min(curAns, initAns + abs(r - fl) - abs(r - fr));
            }
            else if(frSum < brSum)
            {
                curAns = min(curAns, initAns + abs(l - fr) - abs(l - fl));
            }
            else
            {
                assert(false);
            }
            ans = min(ans, curAns);
        }
        cout << ans << '\n';
    }
}
signed main()
{
#ifdef EVAL
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(false);
#endif // EVAL
    solve();
}

Compilation message

bulves.cpp: In function 'void solve()':
bulves.cpp:106:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  106 |         for(int j = 0; j < potIds.size() - 1; ++j)
      |                        ~~^~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 368 KB Output is correct
4 Correct 8 ms 1108 KB Output is correct
5 Correct 13 ms 2004 KB Output is correct
6 Correct 42 ms 4228 KB Output is correct
7 Correct 85 ms 8148 KB Output is correct
8 Correct 62 ms 8148 KB Output is correct
9 Correct 62 ms 8148 KB Output is correct
10 Correct 50 ms 8148 KB Output is correct
11 Correct 48 ms 8144 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 368 KB Output is correct
4 Correct 8 ms 1108 KB Output is correct
5 Correct 13 ms 2004 KB Output is correct
6 Correct 42 ms 4228 KB Output is correct
7 Correct 85 ms 8148 KB Output is correct
8 Correct 62 ms 8148 KB Output is correct
9 Correct 62 ms 8148 KB Output is correct
10 Correct 50 ms 8148 KB Output is correct
11 Correct 48 ms 8144 KB Output is correct
12 Incorrect 33 ms 13164 KB Output isn't correct
13 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Incorrect 0 ms 212 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 368 KB Output is correct
4 Incorrect 0 ms 212 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 368 KB Output is correct
4 Incorrect 0 ms 212 KB Output isn't correct
5 Halted 0 ms 0 KB -