#include <bits/stdc++.h> using namespace std; #define PII pair<int, int> #define VI vector<int> #define VPII vector<PII> #define LL long long #define LD long double #define f first #define s second #define MP make_pair #define PB push_back #define ALL(c) (c).begin(), (c).end() #define SIZ(c) (int)(c).size() #define REP(i, n) for(int i = 0; i < (int)(n); ++i) #define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i) #define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i) #define Sim template<class n Sim, class s> ostream & operator << (ostream &p, pair<n, s> x) {return p << "<" << x.f << ", " << x.s << ">";} Sim> auto operator << (ostream &p, n y) -> typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type {int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";} void dor() {cerr << endl;} Sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);} Sim, class s> void mini(n &p, s y) {if(p>y) p = y;} Sim, class s> void maxi(n &p, s y) {if(p<y) p = y;} #ifdef DEB #define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__) #else #define debug(...) #endif #define I(x) #x " = ", (x), " " #define A(a, i) #a "[" #i " = ", i, "] = ", a[i], " " const int MXN = 303; VI V[MXN]; int res[MXN]; int nxt[MXN]; bool removed[MXN]; VI calc_longest(int n) { FOR(i, 1, n) { res[i] = 0; nxt[i] = 0; } FORD(x, n, 1) { if(removed[x]) continue; for(auto i : V[x]) { if(res[x] < res[i]) { res[x] = res[i]; nxt[x] = i; } } res[x]++; } int idx = 1; FOR(i, 1, n) if(res[idx] < res[i]) idx = i; VI result; int siz = res[idx]; REP(i, siz) { result.PB(idx); idx = nxt[idx]; } return result; } map<VI, int> memo; int solve(int n, int k) { if(k == 0)return calc_longest(n).size(); // check if calculeted prevously VI rem; FOR(i, 1, n) if(removed[i]) rem.PB(i); if(memo.count(rem))return memo[rem]; // VI candidates = calc_longest(n); int res = candidates.size(); for(auto i : candidates) { removed[i] = 1; int r = solve(n, k-1); mini(res, r); removed[i] = 0; } return memo[rem] = res; } int main() { int n, m, k; cin >> n >> m >> k; REP(i, m) { int a, b; cin >> a >> b; V[a].PB(b); } cout << solve(n, k) << endl; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 | #include <bits/stdc++.h> using namespace std; #define PII pair<int, int> #define VI vector<int> #define VPII vector<PII> #define LL long long #define LD long double #define f first #define s second #define MP make_pair #define PB push_back #define ALL(c) (c).begin(), (c).end() #define SIZ(c) (int)(c).size() #define REP(i, n) for(int i = 0; i < (int)(n); ++i) #define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i) #define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i) #define Sim template<class n Sim, class s> ostream & operator << (ostream &p, pair<n, s> x) {return p << "<" << x.f << ", " << x.s << ">";} Sim> auto operator << (ostream &p, n y) -> typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type {int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";} void dor() {cerr << endl;} Sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);} Sim, class s> void mini(n &p, s y) {if(p>y) p = y;} Sim, class s> void maxi(n &p, s y) {if(p<y) p = y;} #ifdef DEB #define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__) #else #define debug(...) #endif #define I(x) #x " = ", (x), " " #define A(a, i) #a "[" #i " = ", i, "] = ", a[i], " " const int MXN = 303; VI V[MXN]; int res[MXN]; int nxt[MXN]; bool removed[MXN]; VI calc_longest(int n) { FOR(i, 1, n) { res[i] = 0; nxt[i] = 0; } FORD(x, n, 1) { if(removed[x]) continue; for(auto i : V[x]) { if(res[x] < res[i]) { res[x] = res[i]; nxt[x] = i; } } res[x]++; } int idx = 1; FOR(i, 1, n) if(res[idx] < res[i]) idx = i; VI result; int siz = res[idx]; REP(i, siz) { result.PB(idx); idx = nxt[idx]; } return result; } map<VI, int> memo; int solve(int n, int k) { if(k == 0)return calc_longest(n).size(); // check if calculeted prevously VI rem; FOR(i, 1, n) if(removed[i]) rem.PB(i); if(memo.count(rem))return memo[rem]; // VI candidates = calc_longest(n); int res = candidates.size(); for(auto i : candidates) { removed[i] = 1; int r = solve(n, k-1); mini(res, r); removed[i] = 0; } return memo[rem] = res; } int main() { int n, m, k; cin >> n >> m >> k; REP(i, m) { int a, b; cin >> a >> b; V[a].PB(b); } cout << solve(n, k) << endl; } |