Submission #116956

# Submission time Handle Problem Language Result Execution time Memory
116956 2019-06-14T08:54:41 Z pzdba Highway Tolls (IOI18_highway) C++14
Compilation error
0 ms 0 KB
#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
vector<pii> g[90005];
int depth[90005], par[90005];
vector<int> ud[90005];

LL ask(std::vector<int> w);
void answer(int s, int t);
void dfs(int u, int p, int j, int d){
    depth[u] = d;
    par[u] = j;
    ud[d].push_back(u);
    for(int i=0;i<g[u].size();i++){
        int v = g[u][i].first, j = g[u][i].second;
        if(v == p) continue;
        dfs(v, u, j, d+1);
    }
}
void find_pair(int n, std::vector<int> u, std::vector<int> v, int a, int b){
    int m = u.size();
    for(int i=0;i<m;i++){
        int a = u[i], b = v[i];
        g[a].push_back(pii(b, i));
        g[b].push_back(pii(a, i));
    }
    dfs(0, -1, 0, 0);
    vector<int> w;
    w.resize(m);
    LL base = ask(w);
    int lo = 1, hi = n, dd = 0, s = 0, t = 0;
    while(lo <= hi){
        int mid = (lo+hi)/2;
        for(int i=0;i<m;i++) w[i] = 0;
        for(int j=mid;j<=n;j++){
            for(int k=0;k<ud[j].size();j++){
                int u = ud[j][k];
                w[par[u]] = 1;
            }
        }
        LL tmp = ask(w);
        if(tmp > base) lo = mid+1, dd = mid;
        else hi = mid-1;
    }
    lo = 0, hi = ud[dd].size()-1;
    while(lo <= hi){
        int mid = (lo+hi)/2;
        for(int i=0;i<m;i++) w[i] = 0;
        for(int j=0;j<=mid;j++){
            int u = ud[dd][j];
            w[par[u]] = 1;
        }
        LL tmp = ask(w);
        if(tmp > base) hi = mid-1, s = ud[dd][mid];
        else lo = mid+1;
    }
    for(int i=0;i<=n;i++) ud[i].clear();
    dfs(s, -1, 0, 0);
    lo = 1, hi = n;
    while(lo <= hi){
        int mid = (lo+hi)/2;
        for(int i=0;i<m;i++) w[i] = 0;
        for(int j=mid;j<=n;j++){
            for(int k=0;k<ud[j].size();j++){
                int u = ud[j][k];
                w[par[u]] = 1;
            }
        }
        LL tmp = ask(w);
        if(tmp > base) lo = mid+1, dd = mid;
        else hi = mid-1;
    }
    lo = 0, hi = ud[dd].size()-1;
    while(lo <= hi){
        int mid = (lo+hi)/2;
        for(int i=0;i<m;i++) w[i] = 0;
        for(int j=0;j<=mid;j++){
            int u = ud[dd][j];
            w[par[u]] = 1;
        }
        LL tmp = ask(w);
        if(tmp > base) hi = mid-1, t = ud[dd][mid];
        else lo = mid+1;
    }
    answer(s, t);
}

Compilation message

highway.cpp: In function 'void dfs(int, int, int, int)':
highway.cpp:15:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[u].size();i++){
                 ~^~~~~~~~~~~~
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:37:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int k=0;k<ud[j].size();j++){
                         ~^~~~~~~~~~~~~
highway.cpp:65:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int k=0;k<ud[j].size();j++){
                         ~^~~~~~~~~~~~~
/tmp/ccx2Aqja.o: In function `find_pair(int, std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >, int, int)':
highway.cpp:(.text+0x27a): undefined reference to `ask(std::vector<int, std::allocator<int> >)'
highway.cpp:(.text+0x3d0): undefined reference to `ask(std::vector<int, std::allocator<int> >)'
highway.cpp:(.text+0x529): undefined reference to `ask(std::vector<int, std::allocator<int> >)'
highway.cpp:(.text+0x6d0): undefined reference to `ask(std::vector<int, std::allocator<int> >)'
highway.cpp:(.text+0x829): undefined reference to `ask(std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status