제출 #659065

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
659065		ansgar	Mecho (IOI09_mecho)	C++17	17 / 100	87 ms	22328 KiB

mecho

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define vi vector<int>
#define vvi vector<vi>
#define pii pair<int,int>
#define vpii vector<pii>
#define vvpii vector<vpii>
#define vb vector<bool>
#define vc vector<char>
#define vvc vector<vc>
#define vvb vector<vb>
#define si set<int>
#define mii map<int,int>

const int mod=1e9+7;
const int N=2e5+1;
const int LN=LLONG_MAX/10;
vvc L;
int n,k;
vvi Bees;
vvi Bear;
vvpii p;
vpii BeesLoc;
bool inside(int y,int x){
    return (y>=0 and y<n and x>=0 and x<n and L[y][x]!='T');
}
void bfsBees(){
    queue<pii> Q;
    for(auto B : BeesLoc){
        Q.push(B);
        Bees[B.first][B.second]=-1;
    }
    while(Q.size()){
        auto B=Q.front();
        int x=B.second;
        int y=B.first;
        Q.pop();
        if(inside(y-1,x) and Bees[y-1][x]>Bees[y][x]+1){
            Bees[y-1][x]=Bees[y][x]+1;
            Q.push({y-1,x});
        }
        if(inside(y+1,x) and Bees[y+1][x]>Bees[y][x]+1){
            Bees[y+1][x]=Bees[y][x]+1;
            Q.push({y+1,x});
        }
        if(inside(y,x-1) and Bees[y][x-1]>Bees[y][x]+1){
            Bees[y][x-1]=Bees[y][x]+1;
            Q.push({y,x-1});
        }
        if(inside(y,x+1) and Bees[y][x+1]>Bees[y][x]+1){
            Bees[y][x+1]=Bees[y][x]+1;
            Q.push({y,x+1});
        }
    }
}
void bfsBear(int sy,int sx){
    queue<pii> Q;
    Q.push({sy,sx});
    Bear[sy][sx]=0;
    p[sy][sx]={sy,sx};
    while(Q.size()){
        auto B=Q.front();
        int x=B.second;
        int y=B.first;
        Q.pop();
        if(inside(y-1,x) and Bear[y-1][x]>Bear[y][x]+1){
            Bear[y-1][x]=Bear[y][x]+1;
            p[y-1][x]={y,x};
            Q.push({y-1,x});
        }
        if(inside(y+1,x) and Bear[y+1][x]>Bear[y][x]+1){
            Bear[y+1][x]=Bear[y][x]+1;
            p[y+1][x]={y,x};
            Q.push({y+1,x});
        }
        if(inside(y,x-1) and Bear[y][x-1]>Bear[y][x]+1){
            Bear[y][x-1]=Bear[y][x]+1;
            p[y][x-1]={y,x};
            Q.push({y,x-1});
        }
        if(inside(y,x+1) and Bear[y][x+1]>Bear[y][x]+1){
            Bear[y][x+1]=Bear[y][x]+1;
            p[y][x+1]={y,x};
            Q.push({y,x+1});
        }
    }
}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin>>n>>k;
    L=vvc(n,vc(n));
    Bear=vvi(n,vi(n,LN));
    Bees=vvi(n,vi(n,LN));
    p=vvpii(n,vpii(n,{-1,-1}));
    int sx,sy,ex,ey;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            cin>>L[i][j];
            if(L[i][j]=='M')sy=i,sx=j;
            if(L[i][j]=='D')ey=i,ex=j;
            if(L[i][j]=='H')BeesLoc.emplace_back(i,j);
        }
    }
    bfsBees();

    bfsBear(sy,sx);
    int sol=LN;
    int aux=ey;
    if(p[ex][ey].first==-1){
        cout<<"-1";
        return 0;
    }
    ey=p[ey][ex].first;
    ex=p[aux][ex].second;
    while(p[ey][ex].first!=ey or p[ey][ex].second!=ex){
        //cout<<ex+1<<" "<<n-ey<<endl;
        //cout<<Bear[ey][ex]<<" "<<Bees[ey][ex]<<endl<<endl;
        sol=min(sol,Bees[ey][ex]-((Bear[ey][ex]-1)/k));
        aux=ey;
        ey=p[ey][ex].first;
        ex=p[aux][ex].second;
    }
    cout<<sol;
}

컴파일 시 표준 에러 (stderr) 메시지

mecho.cpp: In function 'int main()':
mecho.cpp:112:16: warning: 'ey' may be used uninitialized in this function [-Wmaybe-uninitialized]
  112 |     if(p[ex][ey].first==-1){
      |                ^
mecho.cpp:112:12: warning: 'ex' may be used uninitialized in this function [-Wmaybe-uninitialized]
  112 |     if(p[ex][ey].first==-1){
      |            ^
mecho.cpp:109:12: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
  109 |     bfsBear(sy,sx);
      |     ~~~~~~~^~~~~~~
mecho.cpp:109:12: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 17 / 100