Submission #932674

#	Time	Username	Problem	Language	Result	Execution time	Memory
932674		VinhLuu	Street Lamps (APIO19_street_lamps)	C++17	60 / 100	136 ms	33952 KiB

street_lamps

// REPUTATION RATING =

#include <bits/stdc++.h>
#define int long long
#define ll long long
#define fi first
#define se second
#define pb push_back
using namespace std;

typedef pair<int,int> pii;
typedef tuple<int,int,int> tp;
const int N = 3e5 + 5;
//const int oo = 1e9;
const int mod = 1e9 + 7;

int n, q, a[N], L[N], R[N], X[N];
string s, T[N];

namespace sub1{
    int m[105][105];
    void solve(){
        for(int i = 1; i <= n; i ++) m[1][i] = a[i];
        for(int t = 1; t <= q; t ++){
            string type; cin >> type;
            if(type[0] == 't'){
                int x; cin >> x;
                a[x] = 1 - a[x];
            }else{
                int l, r, ans = 0; cin >> l >> r;
                for(int j = 1; j <= t; j ++){
                    bool ff = true;
                    for(int i = l; i < r; i ++) if(m[j][i] == 0){
                        ff = false;
                        break;
                    }
                    ans += ff;
                }
                cout << ans << "\n";
            }
            for(int i = 1;i <= n; i ++) m[t + 1][i] = a[i];
        }
    }
}

namespace sub2{
    bool on[N];
    int cnt[N], f[N];
    void solve(){
        for(int i = 1; i <= n; i ++){
            if(a[i] == 1){
                f[i] = 1;
                on[i] = true;
            }else{
                on[i] = false;
                f[i] = -1;
            }
        }
        for(int t = 1; t <= q; t ++){
            string type = T[t];
            if(type[0] == 't'){
                int x = X[t];
                if(on[x]){
                    cnt[x] += t - f[x] + 1;
                }else{
                    f[x] = t + 1;
                }
                on[x] = 1 - on[x];
            }else{
                int l = L[t], r = R[t], ans = 0; cin >> l >> r;
                if(on[l]) cout << cnt[l] + t - f[l] + 1 << "\n";
                else cout << cnt[l] << "\n";
            }
        }
    }
}

namespace sub3{
    bool on[N];
    int cnt[N], f[N], st[N << 1];
    int get(int l,int r){
        r++;
        int ret = 1;
        for(l += n - 1, r += n - 1; l < r; l /= 2, r /= 2){
            if(l & 1) ret = max(ret, st[l ++]);
            if(r & 1) ret = max(ret, st[-- r]);
        }
        return ret;
    }
    void solve(){
        for(int i = 1; i <= n; i ++){
            if(a[i] == 1){
                f[i] = 1;
                on[i] = true;
            }else{
                on[i] = false;
                f[i] = 1e9;
            }
        }
        for(int t = 1; t <= q; t ++){
            string type = T[t];
            if(type[0] == 't'){
                int x = X[t]; //cin >> x;
                f[x] = t + 1;
            }
        }
        for(int i = 1; i <= n; i ++) st[i + n - 1] = f[i];
        for(int i = n - 1; i >= 1; i --) st[i] = max(st[i << 1], st[i << 1|1]);
        for(int t = 1; t <= q; t ++){
            string type = T[t];
            if(type[0] == 't') continue;

            int l = L[t], r = R[t], ans = 0; cin >> l >> r;
            int u = get(l, r - 1);
            if(u > t) cout << 0 << "\n";
            else cout << t - u + 1 << "\n";
        }
    }
}


#define LOCAL

#ifdef LOCAL
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

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

    cin >> n >> q >> s;
    for(int i = 1; i <= n; i ++) a[i] = s[i - 1] - '0';
    if(n <= 100 && q <= 100)
        sub1 :: solve();
    else{
        bool gg = true;
        for(int i = 1; i <= q; i ++) {
            cin >> T[i];
            if(T[i][0] == 't') cin >> X[i];
            else{
                cin >> L[i] >> R[i];
                if(R[i] - L[i] > 1) gg = false;
            }
        }
        if(gg) sub2 :: solve();
        else
            sub3 :: solve();
    }
}
#endif // LOCAL

Compilation message (stderr)

street_lamps.cpp: In function 'void sub2::solve()':
street_lamps.cpp:70:41: warning: unused variable 'ans' [-Wunused-variable]
   70 |                 int l = L[t], r = R[t], ans = 0; cin >> l >> r;
      |                                         ^~~
street_lamps.cpp: In function 'void sub3::solve()':
street_lamps.cpp:113:37: warning: unused variable 'ans' [-Wunused-variable]
  113 |             int l = L[t], r = R[t], ans = 0; cin >> l >> r;
      |                                     ^~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:130:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  130 |         freopen(task ".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
street_lamps.cpp:131:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  131 |         freopen(task ".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20