Submission #885112

#	Time	Username	Problem	Language	Result	Execution time	Memory
885112		vjudge1	Difference (POI11_roz)	C++17	100 / 100	582 ms	13572 KiB

roz

// Author : Hoang Van Tra - HSGS Bac Giang
// Train VOI 2023 - 2024

#include <bits/stdc++.h>

using namespace std;

// -------------------------------------------------------INDEF-----------------------------------------------------------------------
#define For(i,a,b) for(int i = a; i <= b; i++)
#define Ford(i,a,b) for(int i = a; i >= b; i--)
#define ll long long
#define ii pair<int,int>
#define fi first
#define se second
#define pb push_back
#define all(v) v.begin(),v.end()
#define RRH(v) v.resize(unique(all(v)) - v.begin())
const int  N = 1e6+7;
const int M = 1e9+7;
const ll oo = 1e18;
const int block = 708;

int n;
vector<int> id[30];
string s;

// -------------------------------------------------------ENDEF----------------------------------------------------------------------

int32_t main() {
    ios::sync_with_stdio(0); cin.tie(0);

    #define TASK "ssdiff"
    if (fopen (".inp", "r")) {
        freopen (".inp", "r", stdin);
        freopen (".out", "w", stdout);
    }
    if(fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }

    cin >> n >> s;
    s = " " + s;
    For(i, 1, n) {
        id[s[i] - 'a'].push_back(i);
    }

    int res = 0;
    for (int x = 0; x < 26; x++) {
        for (int y = 0; y < 26; y++) {
            if (id[x].empty() || id[y].empty()) continue;
            if (x == y) continue;
            vector<int> a {0};
            int j = 0;
            for (int i: id[x]) {
                while (j < id[y].size() && id[y][j] < i) {
                    a.push_back(-1);
                    j++;
                }
                a.push_back(1);
            }
            while (j < id[y].size()) {
                a.push_back(-1);
                j++;
            }
            int ans = 0, mini = M, last = 0;
            vector<int> pre (a.size(), 0);
            for (int i = 1; i < a.size(); i++) {
                pre[i] = pre[i - 1] + a[i];
                if (i > 1 && a[i] != a[i - 1]) {
                    for (int j = last; j < i - 1; j++) {
                        mini = min(mini, pre[j]);
                    }
                    last = i - 1;
                }
                ans = max(ans, pre[i] - mini);
            }
            res = max(res, ans);
        }
    }
    cout << res;

    return 0;
}

Compilation message (stderr)

roz.cpp: In function 'int32_t main()':
roz.cpp:56:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |                 while (j < id[y].size() && id[y][j] < i) {
      |                        ~~^~~~~~~~~~~~~~
roz.cpp:62:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |             while (j < id[y].size()) {
      |                    ~~^~~~~~~~~~~~~~
roz.cpp:68:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |             for (int i = 1; i < a.size(); i++) {
      |                             ~~^~~~~~~~~~
roz.cpp:34:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         freopen (".inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~
roz.cpp:35:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |         freopen (".out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
roz.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen(TASK".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
roz.cpp:39:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |         freopen(TASK".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10