bzoj 1293: [SCOI2009]生日礼物
思路：尺取一下
1 #include<bits/stdc++.h> 2 #define LL long long 3 #define fi first 4 #define se second 5 #define mk make_pair 6 #define pii pair<int,int> 7 #define piii pair<int, pair<int,int>> 8 9 using namespace std; 10 11 const int N = 1e6 + 7; 12 const int M = 1e4 + 7; 13 const int inf = 0x3f3f3f3f; 14 const LL INF = 0x3f3f3f3f3f3f3f3f; 15 const int mod = 1e9 + 7; 16 17 int n, k, hs[N], tot, cnt[66]; 18 vector<int> vec[66]; 19 vector<int> w[N]; 20 LL a[N]; 21 22 int check() { 23 int l = 0, r = 0, ans = inf; 24 LL ret = 0; 25 while(r < tot) { 26 while(ret + 1 != 1ll << k && r < tot) { 27 for(int j = 0; j < w[r].size(); j++) { 28 int u = w[r][j]; 29 if(!cnt[u]) { 30 ret |= 1ll << u; 31 } 32 cnt[u]++; 33 } 34 r++; 35 } 36 if(ret + 1 == 1ll << k) ans = min(ans, hs[r - 1] - hs[l]); 37 else break; 38 39 for(int j = 0; j < w[l].size(); j++) { 40 int u = w[l][j]; 41 if(cnt[u] == 1) { 42 ret ^= 1ll << u; 43 } 44 cnt[u]--; 45 } 46 l++; 47 } 48 return ans; 49 } 50 51 int main() { 52 scanf("%d%d", &n, &k); 53 for(int i = 0; i < k; i++) { 54 int num; scanf("%d", &num); 55 while(num--) { 56 int x; scanf("%d", &x); 57 hs[tot++] = x; 58 vec[i].push_back(x); 59 } 60 } 61 62 sort(hs, hs + tot); 63 tot = unique(hs, hs + tot) - hs; 64 for(int i = 0; i < k; i++) { 65 for(int j = 0; j < vec[i].size(); j++) { 66 int pos = lower_bound(hs, hs + tot, vec[i][j]) - hs; 67 w[pos].push_back(i); 68 } 69 } 70 int ans = check(); 71 printf("%d\n", ans); 72 return 0; 73 } 74 75 /* 76 */
