Submission #395671

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
395671	2021-04-28T18:01:18 Z	MarcoMeijer	Islands (IOI08_islands)	C++14	Compilation error	0 ms	0 KB

islands

#include <bits/stdc++.h>
using namespace std;
 
// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e18
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
 
// input
template<class T> void IN(T& x) {cin >> x;}
template<class H, class... T> void IN(H& h, T&... t) {IN(h); IN(t...); }
 
// output
template<class T1, class T2> void OUT(const pair<T1,T2>& x);
template<class T> void OUT(const vector<T>& x);
template<class T> void OUT(const T& x) {cout << x;}
template<class H, class... T> void OUT(const H& h, const T&... t) {OUT(h); OUT(t...); }
template<class T1, class T2> void OUT(const pair<T1,T2>& x) {OUT(x.fi,' ',x.se);}
template<class T> void OUT(const vector<T>& x) {RE(i,x.size()) OUT(i==0?"":" ",x[i]);}
template<class... T> void OUTL(const T&... t) {OUT(t..., "\n"); }
template<class H> void OUTLS(const H& h) {OUTL(h); }
template<class H, class... T> void OUTLS(const H& h, const T&... t) {OUT(h,' '); OUTLS(t...); }
 
// dp
template<class T> bool ckmin(T&a, T&b) { bool bl = a > b; a = min(a,b); return bl;}
template<class T> bool ckmax(T&a, T&b) { bool bl = a < b; a = max(a,b); return bl;}
 
void program();
signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    program();
}
 
 
//===================//
//   begin program   //
//===================//
 
const int MX = 1e6+8;
const int N = (1<<20);

int n, edges;
int l[MX];
vii adj[MX];

// finding cycles
bitset<MX> visited;
int cycleStart;
int skippedEdge = -1;
vii cycle;
bool dfsVisit(int u, int pe) {
    if(visited[u]) {
        cycleStart = u;
        skippedEdge = pe;
        return true;
    }
    bool res = false;
    visited[u] = 1;
    RE(i,adj[u].size()) {
        if(adj[u][i].se == pe || adj[u][i].se == skippedEdge) continue;
        if(!dfsVisit(adj[u][i].fi, adj[u][i].se^1)) continue;
        
        cycle.pb({adj[u][i].fi, l[adj[u][i].se/2]});
        res = u != cycleStart;
    }
    return res;
}

// finding depth
ll curBest = 0;
void combine(lll& x, ll y) {x = {max(x.fi,y), max(min(x.fi,y),x.se)};}
bitset<MX> visited2;
ll dfsDepth(int u) {
    lll p = {0,0};
    visited2[u] = 1;
    RE(i,adj[u].size()) {
        if(visited2[adj[u][i].fi]) continue;
        p = combine(p,l[adj[u][i].se/2] + dfsDepth(adj[u][i].fi));
    }
    curBest = max(curBest, p.fi + p.se);
    return p.fi;
}

void program() {
    IN(n);
    RE1(b,n) {
        int a; IN(a,l[b-1]);
        adj[a].pb({b,edges++});
        adj[b].pb({a,edges++});
    }
    RE1(i,n) adj[i].shrink_to_fit();

    ll ans = 0;
    RE1(i,n) {
        if(visited[i]) continue;

        // find the cycle
        curBest = 0;
        cycle.clear(); cycle.shrink_to_fit();
        dfsVisit(i,-1);

        // fill a, b and c
        ll m = cycle.size(), totB = 0;
        FOR(u,cycle) totB += u.se;

        ll curB = totB;
        ll bestSum1 = -INF, bestSum2 = -INF;
        REV(i,0,m) {
            curB -= cycle[i].se;
            visited2[cycle[i].fi] = 0;
            visited2[cycle[(i+1+m)%m].fi] = 1;
            visited2[cycle[(i-1+m)%m].fi] = 1;
            ll C = dfsDepth(cycle[i].fi);
            curBest  = max(curBest ,        bestSum1 - curB + C);
            curBest  = max(curBest , totB + bestSum2 + curB + C);
            bestSum1 = max(bestSum1,  curB + C);
            bestSum2 = max(bestSum2, -curB + C);
        }
        ans += curBest;
    }
    OUTL(ans);
}

Compilation message

islands.cpp: In function 'll dfsDepth(int)':
islands.cpp:101:65: error: no match for 'operator=' (operand types are 'lll' {aka 'std::pair<long long int, long long int>'} and 'void')
  101 |         p = combine(p,l[adj[u][i].se/2] + dfsDepth(adj[u][i].fi));
      |                                                                 ^
In file included from /usr/include/c++/9/bits/stl_algobase.h:64,
                 from /usr/include/c++/9/bits/char_traits.h:39,
                 from /usr/include/c++/9/ios:40,
                 from /usr/include/c++/9/istream:38,
                 from /usr/include/c++/9/sstream:38,
                 from /usr/include/c++/9/complex:45,
                 from /usr/include/c++/9/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/9/bits/stdc++.h:54,
                 from islands.cpp:1:
/usr/include/c++/9/bits/stl_pair.h:378:7: note: candidate: 'std::pair<_T1, _T2>& std::pair<_T1, _T2>::operator=(typename std::conditional<std::__and_<std::is_copy_assignable<_T1>, std::is_copy_assignable<_T2> >::value, const std::pair<_T1, _T2>&, const std::__nonesuch_no_braces&>::type) [with _T1 = long long int; _T2 = long long int; typename std::conditional<std::__and_<std::is_copy_assignable<_T1>, std::is_copy_assignable<_T2> >::value, const std::pair<_T1, _T2>&, const std::__nonesuch_no_braces&>::type = const std::pair<long long int, long long int>&]'
  378 |       operator=(typename conditional<
      |       ^~~~~~~~
/usr/include/c++/9/bits/stl_pair.h:381:51: note:   no known conversion for argument 1 from 'void' to 'std::conditional<true, const std::pair<long long int, long long int>&, const std::__nonesuch_no_braces&>::type' {aka 'const std::pair<long long int, long long int>&'}
  378 |       operator=(typename conditional<
      |                 ~~~~~~~~~~~~~~~~~~~~~              
  379 |   __and_<is_copy_assignable<_T1>,
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                  
  380 |          is_copy_assignable<_T2>>::value,
      |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~          
  381 |   const pair&, const __nonesuch_no_braces&>::type __p)
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/9/bits/stl_pair.h:389:7: note: candidate: 'std::pair<_T1, _T2>& std::pair<_T1, _T2>::operator=(typename std::conditional<std::__and_<std::is_move_assignable<_Tp>, std::is_move_assignable<_T2> >::value, std::pair<_T1, _T2>&&, std::__nonesuch_no_braces&&>::type) [with _T1 = long long int; _T2 = long long int; typename std::conditional<std::__and_<std::is_move_assignable<_Tp>, std::is_move_assignable<_T2> >::value, std::pair<_T1, _T2>&&, std::__nonesuch_no_braces&&>::type = std::pair<long long int, long long int>&&]'
  389 |       operator=(typename conditional<
      |       ^~~~~~~~
/usr/include/c++/9/bits/stl_pair.h:392:41: note:   no known conversion for argument 1 from 'void' to 'std::conditional<true, std::pair<long long int, long long int>&&, std::__nonesuch_no_braces&&>::type' {aka 'std::pair<long long int, long long int>&&'}
  389 |       operator=(typename conditional<
      |                 ~~~~~~~~~~~~~~~~~~~~~    
  390 |   __and_<is_move_assignable<_T1>,
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~        
  391 |          is_move_assignable<_T2>>::value,
      |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  392 |   pair&&, __nonesuch_no_braces&&>::type __p)
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/9/bits/stl_pair.h:405:2: note: candidate: 'template<class _U1, class _U2> typename std::enable_if<std::__and_<std::is_assignable<_T1&, const _U1&>, std::is_assignable<_T2&, const _U2&> >::value, std::pair<_T1, _T2>&>::type std::pair<_T1, _T2>::operator=(const std::pair<_U1, _U2>&) [with _U1 = _U1; _U2 = _U2; _T1 = long long int; _T2 = long long int]'
  405 |  operator=(const pair<_U1, _U2>& __p)
      |  ^~~~~~~~
/usr/include/c++/9/bits/stl_pair.h:405:2: note:   template argument deduction/substitution failed:
islands.cpp:101:65: note:   mismatched types 'const std::pair<_T1, _T2>' and 'void'
  101 |         p = combine(p,l[adj[u][i].se/2] + dfsDepth(adj[u][i].fi));
      |                                                                 ^
In file included from /usr/include/c++/9/bits/stl_algobase.h:64,
                 from /usr/include/c++/9/bits/char_traits.h:39,
                 from /usr/include/c++/9/ios:40,
                 from /usr/include/c++/9/istream:38,
                 from /usr/include/c++/9/sstream:38,
                 from /usr/include/c++/9/complex:45,
                 from /usr/include/c++/9/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/9/bits/stdc++.h:54,
                 from islands.cpp:1:
/usr/include/c++/9/bits/stl_pair.h:416:2: note: candidate: 'template<class _U1, class _U2> typename std::enable_if<std::__and_<std::is_assignable<_T1&, _U1&&>, std::is_assignable<_T2&, _U2&&> >::value, std::pair<_T1, _T2>&>::type std::pair<_T1, _T2>::operator=(std::pair<_U1, _U2>&&) [with _U1 = _U1; _U2 = _U2; _T1 = long long int; _T2 = long long int]'
  416 |  operator=(pair<_U1, _U2>&& __p)
      |  ^~~~~~~~
/usr/include/c++/9/bits/stl_pair.h:416:2: note:   template argument deduction/substitution failed:
islands.cpp:101:65: note:   mismatched types 'std::pair<_T1, _T2>' and 'void'
  101 |         p = combine(p,l[adj[u][i].se/2] + dfsDepth(adj[u][i].fi));
      |                                                                 ^