Submission #996700

#	Time	Username	Problem	Language	Result	Execution time	Memory
996700		yeediot	Trains (BOI24_trains)	C++17	100 / 100	303 ms	250844 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
#define __lg(x) 63-__builtin_clzll(x)
#define pow2(x) (1LL<<x)
void __print(int x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
#ifdef local
void CHECK();
void setio(){
    freopen("/Users/iantsai/cpp/input.txt","r",stdin);
    freopen("/Users/iantsai/cpp/output.txt","w",stdout);
}
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
void setio(){}
#define debug(x...)
#endif
#define TOI_is_so_de ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);setio();
const int mxn = 1e5+5, siz = sqrt(mxn), mod = 1e9+7;
int d[mxn], x[mxn];
void add(int &a,int b){
    a+=b;
    a%=mod;
    if(a<0)a+=mod;
}
signed main(){
    TOI_is_so_de;
    int n;
    cin >> n;
    int dp[n+1];
    memset(dp,0,sizeof(dp));
    int s[n+1][siz+1];
    memset(s,0,sizeof(s));
    for(int i=1;i<=n;i++){
        cin >> d[i] >> x[i];
    }
    dp[1] = 1;
    int ans = 0;
    for(int i=1;i<=n;i++){
        for(int j=1;j<siz;j++){
            if(i-j>=1){
                add(s[i][j],s[i-j][j]);
            }
            add(dp[i],s[i][j]);
        }
        if(d[i]>=siz){
            for(int j=1;j<=x[i] and i+d[i]*j<=n;j++){
                add(dp[i+d[i]*j],dp[i]);
            }
        }
        else{
            if(x[i] and i+d[i]<=n)add(s[i+d[i]][d[i]],dp[i]);
            if(x[i] and i+d[i]*(x[i]+1)<=n){
                add(s[i+d[i]*(x[i]+1)][d[i]],-dp[i]);
            }
        }
        add(ans,dp[i]);
        debug(dp[i]);
    }
    cout << ans << '\n';
    #ifdef local
    CHECK();
    #endif
}
/*
input:
 
*/
#ifdef local
void CHECK(){
    cerr << "\n[Time]: " << 1000.0 * clock() / CLOCKS_PER_SEC << " ms.\n";
     function<bool(string,string)> compareFiles = [](string p1, string p2)->bool {
         std::ifstream file1(p1);
         std::ifstream file2(p2);
         if (!file1.is_open() || !file2.is_open())return false;
         std::string line1, line2;
         while (getline(file1, line1) && getline(file2, line2)) {
             if (line1 != line2)return false;
         }
         int cnta=0,cntb=0;
         while(getline(file1,line1))cnta++;
         while(getline(file2,line2))cntb++;
         return cntb-cnta<=1;
     };
     bool check = compareFiles("output.txt","expected.txt");
     if (check) cerr<<"ACCEPTED\n";
     else cerr<<"WRONG ANSWER!\n";
}
#else
#endif



 

Compilation message (stderr)

Main.cpp: In function 'void setIO(std::string)':
Main.cpp:35:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:36:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 13 / 13
• Subtask 3: 16 / 16
• Subtask 4: 34 / 34
• Subtask 5: 29 / 29