#include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> #define ll long long #define ld long double #define ull unsigned long long #define ff first #define ss second #define pii pair<int,int> #define pll pair<long long, long long> #define vi vector<int> #define vl vector<long long> #define pb push_back #define rep(i, b) for(int i = 0; i < (b); ++i) #define rep2(i,a,b) for(int i = a; i <= (b); ++i) #define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c) #define count_bits(x) __builtin_popcountll((x)) #define all(x) (x).begin(),(x).end() #define siz(x) (int)(x).size() #define forall(it,x) for(auto& it:(x)) using namespace __gnu_pbds; using namespace std; typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set; //mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());} //ll los(ll a, ll b) {return a + (mt() % (b-a+1));} const int INF = 1e9+50; const ll INF_L = 1e18+40; const ll MOD = 1e9+7; int pref1[8001]; int pref2[8001]; int main() { ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); //random_start(); int n,k,t; cin >> n >> k >> t; string s; cin >> s; int total_meet = 0; s = "3" + s; forall(it,s) { if(it != '3') total_meet++; } rep2(i,1,n) { pref1[i] = pref1[i-1]; pref2[i] = pref2[i-1]; if(s[i] == '1') pref1[i]++; if(s[i] == '2') { pref2[i]++; pref1[i]++; } } if(k >= total_meet) { cout << n << "\n"; return 0; } int ans = -1; if(pref2[n] >= (total_meet-k)) { ans = n - max(0,total_meet-k); } rep2(t1,1,n-t-t+1) { rep2(t2,t1+t,n-t+1) { if(pref1[t2-1] - pref1[t1+t-1] + pref2[t1-1] + pref2[n] - pref2[t2+t-1] >= (total_meet-k)) { // cout << t1 << " " << t2 << " " << (n - (t2+t- t1)) - max(0,(total_meet-k) - (pref1[t2-1] - pref1[t1+t-1])) << " " << pref1[t2-1] - pref1[t1+t-1] << " " << total_meet << " " << pref2[t1-1] + pref2[n] - pref2[t2+t-1] << "\n"; ans = max(ans,(n - (t2+t- t1)) - max(0,(total_meet-k) - (pref1[t2-1] - pref1[t1+t-1]))); } } } cout << ans << "\n"; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 | #include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> #define ll long long #define ld long double #define ull unsigned long long #define ff first #define ss second #define pii pair<int,int> #define pll pair<long long, long long> #define vi vector<int> #define vl vector<long long> #define pb push_back #define rep(i, b) for(int i = 0; i < (b); ++i) #define rep2(i,a,b) for(int i = a; i <= (b); ++i) #define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c) #define count_bits(x) __builtin_popcountll((x)) #define all(x) (x).begin(),(x).end() #define siz(x) (int)(x).size() #define forall(it,x) for(auto& it:(x)) using namespace __gnu_pbds; using namespace std; typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set; //mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());} //ll los(ll a, ll b) {return a + (mt() % (b-a+1));} const int INF = 1e9+50; const ll INF_L = 1e18+40; const ll MOD = 1e9+7; int pref1[8001]; int pref2[8001]; int main() { ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); //random_start(); int n,k,t; cin >> n >> k >> t; string s; cin >> s; int total_meet = 0; s = "3" + s; forall(it,s) { if(it != '3') total_meet++; } rep2(i,1,n) { pref1[i] = pref1[i-1]; pref2[i] = pref2[i-1]; if(s[i] == '1') pref1[i]++; if(s[i] == '2') { pref2[i]++; pref1[i]++; } } if(k >= total_meet) { cout << n << "\n"; return 0; } int ans = -1; if(pref2[n] >= (total_meet-k)) { ans = n - max(0,total_meet-k); } rep2(t1,1,n-t-t+1) { rep2(t2,t1+t,n-t+1) { if(pref1[t2-1] - pref1[t1+t-1] + pref2[t1-1] + pref2[n] - pref2[t2+t-1] >= (total_meet-k)) { // cout << t1 << " " << t2 << " " << (n - (t2+t- t1)) - max(0,(total_meet-k) - (pref1[t2-1] - pref1[t1+t-1])) << " " << pref1[t2-1] - pref1[t1+t-1] << " " << total_meet << " " << pref2[t1-1] + pref2[n] - pref2[t2+t-1] << "\n"; ans = max(ans,(n - (t2+t- t1)) - max(0,(total_meet-k) - (pref1[t2-1] - pref1[t1+t-1]))); } } } cout << ans << "\n"; } |