// Artur Kraska, II UWr #include <algorithm> #include <iostream> #include <cstdio> #include <cstdlib> #include <cstring> #include <vector> #include <cmath> #include <list> #include <set> #include <map> #define forr(i, n) for(int i=0; i<n; i++) #define FOREACH(iter, coll) for(typeof(coll.begin()) iter = coll.begin(); iter != coll.end(); ++iter) #define FOREACHR(iter, coll) for(typeof(coll.rbegin()) iter = coll.rbegin(); iter != coll.rend(); ++iter) #define lbound(P,R,PRED) ({typeof(P) X=P,RRR=(R), PPP = P; while(PPP<RRR) {X = (PPP+(RRR-PPP)/2); if(PRED) RRR = X; else PPP = X+1;} PPP;}) #define testy() int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests) #define CLEAR(tab) memset(tab, 0, sizeof(tab)) #define CONTAIN(el, coll) (coll.find(el) != coll.end()) #define FOR(i, a, b) for(int i=a; i<=b; i++) #define FORD(i, a, b) for(int i=a; i>=b; i--) #define MP make_pair #define PB push_back #define deb(X) X; #define M 1000000007 #define INF 1000000007 using namespace std; int n, m, k, a, b; struct elem { vector <int> l; int odl; int gdzie; bool zly; }; elem tab[1007]; int przelicz() { int maks = 0, nr = -1; FORD(i, n, 1) { if(tab[i].zly) continue; tab[i].odl = 1; for(int j : tab[i].l) if(!tab[j].zly && tab[j].odl >= tab[i].odl) { tab[i].odl = tab[j].odl+1; tab[i].gdzie = j; } if(tab[i].odl > maks) { maks = tab[i].odl; nr = i; } } return nr; } int ruszaj(int ile) { int p = przelicz(); if(ile == 0) { // cout << "wynik to " << tab[p].odl << endl; return p == -1 ? 0 : tab[p].odl; } vector <int> v; v.PB(p); while(tab[p].odl > 1) { p = tab[p].gdzie; v.PB(p); } int res = 1007; for(int el : v) { // cout << "wywala " << el << endl; tab[el].zly = 1; res = min(res, ruszaj(ile-1)); // cout << "przywraca " << el << endl; tab[el].zly = 0; } return res; } int main() { scanf("%d %d %d", &n, &m, &k); forr(i, m) { scanf("%d %d", &a, &b); tab[a].l.PB(b); } int res = (k >= n ? 0 : ruszaj(k)); printf("%d\n", res); return 0; }
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 | // Artur Kraska, II UWr #include <algorithm> #include <iostream> #include <cstdio> #include <cstdlib> #include <cstring> #include <vector> #include <cmath> #include <list> #include <set> #include <map> #define forr(i, n) for(int i=0; i<n; i++) #define FOREACH(iter, coll) for(typeof(coll.begin()) iter = coll.begin(); iter != coll.end(); ++iter) #define FOREACHR(iter, coll) for(typeof(coll.rbegin()) iter = coll.rbegin(); iter != coll.rend(); ++iter) #define lbound(P,R,PRED) ({typeof(P) X=P,RRR=(R), PPP = P; while(PPP<RRR) {X = (PPP+(RRR-PPP)/2); if(PRED) RRR = X; else PPP = X+1;} PPP;}) #define testy() int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests) #define CLEAR(tab) memset(tab, 0, sizeof(tab)) #define CONTAIN(el, coll) (coll.find(el) != coll.end()) #define FOR(i, a, b) for(int i=a; i<=b; i++) #define FORD(i, a, b) for(int i=a; i>=b; i--) #define MP make_pair #define PB push_back #define deb(X) X; #define M 1000000007 #define INF 1000000007 using namespace std; int n, m, k, a, b; struct elem { vector <int> l; int odl; int gdzie; bool zly; }; elem tab[1007]; int przelicz() { int maks = 0, nr = -1; FORD(i, n, 1) { if(tab[i].zly) continue; tab[i].odl = 1; for(int j : tab[i].l) if(!tab[j].zly && tab[j].odl >= tab[i].odl) { tab[i].odl = tab[j].odl+1; tab[i].gdzie = j; } if(tab[i].odl > maks) { maks = tab[i].odl; nr = i; } } return nr; } int ruszaj(int ile) { int p = przelicz(); if(ile == 0) { // cout << "wynik to " << tab[p].odl << endl; return p == -1 ? 0 : tab[p].odl; } vector <int> v; v.PB(p); while(tab[p].odl > 1) { p = tab[p].gdzie; v.PB(p); } int res = 1007; for(int el : v) { // cout << "wywala " << el << endl; tab[el].zly = 1; res = min(res, ruszaj(ile-1)); // cout << "przywraca " << el << endl; tab[el].zly = 0; } return res; } int main() { scanf("%d %d %d", &n, &m, &k); forr(i, m) { scanf("%d %d", &a, &b); tab[a].l.PB(b); } int res = (k >= n ? 0 : ruszaj(k)); printf("%d\n", res); return 0; } |