Submission #935131

#	Time	Username	Problem	Language	Result	Execution time	Memory
935131		cpptowin	Race (IOI11_race)	C++17	Compilation error	0 ms	0 KiB

race

#include<bits/stdc++.h>
#define fo(i,d,c) for(int i=d;i<=c;i++)
#define fod(i,c,d) for(int i=c;i>=d;i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout<<"\n";
#define int long long
#define inf (int)1e18
#define pii pair<int,int>
#define vii vector<pii>
#define lb(x) x&-x
#define bit(i,j) ((i>>j)&1)
#define offbit(i,j) (i^(1<<j))
#define onbit(i,j) (i|(1<<j))
#define vi vector<int>
template <typename T1, typename T2> bool minimize(T1 &a, T2 b){if (a > b) {a = b; return true;} return false;}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b){if (a < b) {a = b; return true;} return false;}
using namespace std;
const int nsqrt = 450;
const int mod = 1e9 + 7;
int n,K;
vii ke[maxn];
int f[maxn];
// centroid decomposition
bool is_remove[maxn];
int sz[maxn];
int ans = inf;
int dfs_size(int u,int parent = -1)
{
    sz[u] = 1;
    for(auto [v,w] : ke[u])
    {
        if(v == parent or is_remove[v]) continue;
        sz[u] += dfs_size(v,u);
    }
    return sz[u];
}
int dfs_centroid(int u,int tree_size,int parent = 0)
{
    for(auto [v,w] : ke[u])
    {
        if(v == parent or is_remove[v]) continue;
        if(2 * sz[v] > tree_size) return dfs_centroid(v,tree_size,u);
    }
    return u;
}
void dfs_dist(int u,int parent,bool get_ans,int len,int edge)
{
    if(len > K) return;
    int val = f[len];
    f[len] = edge;
    for(auto [v,w] : ke[u])
    {
        if(v == parent or is_remove[v]) continue;
        dfs_dist(v,u,get_ans,len + w,edge + 1);
    }
    f[len] = val;
    if(get_ans)
    {
        ans = min(ans,f[K - len] + edge);
    }
    else f[len] = edge;
}
void build_centroid(int u)
{
    int centroid = dfs_centroid(u,dfs_size(u));
    is_remove[centroid] = 1;
    // do sth
    for(auto [v,w] : ke[centroid])
    {
        if(is_remove[v]) continue;
        dfs_dist(v,centroid,1,w,1);
        dfs_dist(v,centroid,0,w,1);
    }
    for(auto [v,w] : ke[centroid])
    {
        if(is_remove[v]) continue;
        build_centroid(v);
    }
}
main()
{
    #define name "TASK"
    if(fopen(name".inp","r"))
    {
       freopen(name".inp","r",stdin);
       freopen(name".out","w",stdout);
    }
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    cin >> n >> K;
    fo(i,1,n - 1)
    {
        int u,v,w;
        cin >> u >> v >> w;
        u++;v++;
        ke[u].pb(v,w);
        ke[v].pb(u,w);
    }
    fo(i,0,maxn - 1) f[i] = inf;
    build_centroid(1);
    cout << (ans == inf ? -1 : ans);
}

Compilation message (stderr)

race.cpp:84:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   84 | main()
      | ^~~~
race.cpp: In function 'int main()':
race.cpp:89:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |        freopen(name".inp","r",stdin);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
race.cpp:90:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |        freopen(name".out","w",stdout);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/cclGfkQl.o: in function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccMLi2bk.o:grader.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccMLi2bk.o: in function `main':
grader.cpp:(.text.startup+0x28): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status