每日水題 11-26

xxb3.1415發表於2020-11-29

文章目錄

ACM Contest and Blackout

ACM Contest and Blackout
次小生成樹裸題

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<queue>
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const double Pi = acos(-1);
namespace io{
  template <typename T> inline void read(T &x) {
    x = 0; T f = 1;char s = getchar();
    for(; !isdigit(s); s = getchar()) if(s == '-') f = -1;
    for(;  isdigit(s); s = getchar()) x = (x << 3) + (x << 1) + (s ^ 48);
    x *= f;
  }
  template <typename T> inline void write(T x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x/10);
    putchar(x%10+'0');
  }
};
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _for(n,m,i) for (register int i = (n); i <  (m); ++i)
#define _rep(n,m,i) for (register int i = (n); i <= (m); ++i)
#define _srep(n,m,i)for (register int i = (n); i >= (m); i--)
#define _sfor(n,m,i)for (register int i = (n); i >  (m); i--)
#define ef(u, i) for(int i = head[u]; i; i = e[i].next)
#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
#define lowbit(x) x & (-x)
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e2+5;
const int M = 1e4+5;
struct node {
  int u, v, w;
  bool operator < (const node &a) const {
    return w < a.w;
  }
}e[M];
int f[N];
int Find(int x) {
  return x == f[x] ? x : f[x] = Find(f[x]);
}

bool brid[M];
int mx[N][N];
vector<int> fv[N];

int main() {
  int t; scanf("%d", &t);
  while(t--) {
    int n, m;
    scanf("%d %d", &n, &m);
    for(int i = 1;  i <= n; ++i) {
      f[i] = i;
      fv[i].clear();
      fv[i].push_back(i);    
    }
    
    
    for(int i = 0; i < m; ++i) {
      brid[i] = 0;
      scanf("%d %d %d", &e[i].u, &e[i].v, &e[i].w);
    }
    sort(e, e + m);
    int num = n-1, ans = 0;
    for(int i = 0; i < m; ++i) {
      int fx = Find(e[i].u), fy = Find(e[i].v);
      if(fx != fy) {
        brid[i] = 1;
        ans += e[i].w;
        if(fv[fx].size() > fv[fy].size()) swap(fx, fy);
        f[fx] = fy;
        for(auto it : fv[fx]) {
          for(auto is : fv[fy]) {
            mx[it][is] = mx[is][it] = e[i].w;
          }
        }
        for(auto it : fv[fx]) {
          fv[fy].push_back(it);
        }
        fv[fx].clear();
        num--;
      }
      if(!num) break;
    } 
    int cans = INF;
    for(int i = 0; i < m; ++i) {
      if(!brid[i]) {
        cans = min(cans, ans - mx[e[i].u][e[i].v] + e[i].w);
      }
    }
    printf("%d %d\n", ans, cans);
  }
	return 0;
}

Clairewd’s message

Clairewd’s message
考察kmp性質。貌似看別人都是用exkmp。

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<queue>
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const double Pi = acos(-1);
namespace io{
  template <typename T> inline void read(T &x) {
    x = 0; T f = 1;char s = getchar();
    for(; !isdigit(s); s = getchar()) if(s == '-') f = -1;
    for(;  isdigit(s); s = getchar()) x = (x << 3) + (x << 1) + (s ^ 48);
    x *= f;
  }
  template <typename T> inline void write(T x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x/10);
    putchar(x%10+'0');
  }
};
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _for(n,m,i) for (register int i = (n); i <  (m); ++i)
#define _rep(n,m,i) for (register int i = (n); i <= (m); ++i)
#define _srep(n,m,i)for (register int i = (n); i >= (m); i--)
#define _sfor(n,m,i)for (register int i = (n); i >  (m); i--)
#define ef(u, i) for(int i = head[u]; i; i = e[i].next)
#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
#define lowbit(x) x & (-x)
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e5+5;
char zh[27], fzh[27];
char s[N*2];
int nx[N*2];
void solve(int m) {
  int n = strlen(s), k = 0;
  for(int i = 1; i < n; ++i) {
    while(k && s[i] != s[k]) k = nx[k];
    if(s[i] == s[k]) k++;
    nx[i+1] = k;
  }
  int len = m - nx[n];
  if(len * 2 < m) { 
    len = m - nx[m];
    k = m / len + (m % len != 0);
    len = (k+1)/2*len;
  } 
  for(int i = 0; i < len; ++i) { 
    s[i+len] = fzh[s[i]-'a'];
  } 
  s[len*2] = '\0';
  printf("%s\n", s);
} 
int main() {
  int t; scanf("%d", &t);
  while(t--) {
    scanf("%s", zh);
    for(int i = 0; i < 26; ++i) {
      fzh[zh[i]-'a'] = i + 'a';
    }
    scanf("%s", s);
    int n = strlen(s);
    s[n] = '#';
    for(int i = 0; i < n; ++i) {
      s[i+n+1] = zh[s[i]-'a'];
    }
    s[n+n+1] = '\0';
    solve(n);
  }
}

Constructing Roads

Constructing Roads
最小生成樹prim

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<queue>
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const double Pi = acos(-1);
namespace io{
  template <typename T> inline void read(T &x) {
    x = 0; T f = 1;char s = getchar();
    for(; !isdigit(s); s = getchar()) if(s == '-') f = -1;
    for(;  isdigit(s); s = getchar()) x = (x << 3) + (x << 1) + (s ^ 48);
    x *= f;
  }
  template <typename T> inline void write(T x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x/10);
    putchar(x%10+'0');
  }
};
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _for(n,m,i) for (register int i = (n); i <  (m); ++i)
#define _rep(n,m,i) for (register int i = (n); i <= (m); ++i)
#define _srep(n,m,i)for (register int i = (n); i >= (m); i--)
#define _sfor(n,m,i)for (register int i = (n); i >  (m); i--)
#define ef(u, i) for(int i = head[u]; i; i = e[i].next)
#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
#define lowbit(x) x & (-x)
#define pii pair<int,int>
#define fi first
#define se second
int a[105][105];
int dis[105];
bool vis[105];
int main() {
  int n; cin >> n;
  for(int i = 1; i <= n; ++i) {
    for(int j = 1; j <= n; ++j) {
      cin >> a[i][j];
    }
  }
  int m, u, v; cin >> m;
  dis[0] = INF;
	while(m--) {
	  cin >> u >> v;
	  a[u][v] = a[v][u] = 0;
  }
  for(int i = 1; i <= n; ++i) dis[i] = a[1][i];
  vis[1] = 1;
  int ans = 0;
  for(int i = 1; i < n; ++i) {
    int j = 0;
    for(int k = 1; k <= n; ++k) {
      if(!vis[k] && dis[k] < dis[j]) {
        j = k;
      }
    }
    if(!j) break;
    vis[j] = 1;
    ans += dis[j];
    for(int k = 1; k <= n; ++k) {
      if(!vis[k] && dis[k] > a[j][k]) {
        dis[k] = a[j][k];
      }
    }
  }
  cout << ans << endl;
  return 0;
}

Mayor’s posters

Mayor’s posters
線段樹+離散化+懶標記

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<queue>
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const double Pi = acos(-1);
namespace io{
  template <typename T> inline void read(T &x) {
    x = 0; T f = 1;char s = getchar();
    for(; !isdigit(s); s = getchar()) if(s == '-') f = -1;
    for(;  isdigit(s); s = getchar()) x = (x << 3) + (x << 1) + (s ^ 48);
    x *= f;
  }
  template <typename T> inline void write(T x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x/10);
    putchar(x%10+'0');
  }
};
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _for(n,m,i) for (register int i = (n); i <  (m); ++i)
#define _rep(n,m,i) for (register int i = (n); i <= (m); ++i)
#define _srep(n,m,i)for (register int i = (n); i >= (m); i--)
#define _sfor(n,m,i)for (register int i = (n); i >  (m); i--)
#define ef(u, i) for(int i = head[u]; i; i = e[i].next)
#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
#define lowbit(x) x & (-x)
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e5+5;
struct node {
  int l, r;
}e[N];
vector<int> ve;
int getid(int x) {
  return lower_bound(ve.begin(), ve.end(), x) - ve.begin() + 1;
}
int T[N<<3], lazy[N<<3];
void build(int rt, int l, int r) {
  T[rt] = lazy[rt] = 0;
  if(l == r) {
    return ;
  }
  int mid = l + r >> 1;
  build(lson); build(rson);
}
void down(int rt) {
  if(lazy[rt]) {
    T[rt<<1] = lazy[rt];
    lazy[rt<<1] = lazy[rt];
    
    T[rt<<1|1] = lazy[rt];
    lazy[rt<<1|1] = lazy[rt];
    lazy[rt] = 0;
  }
}
void upd(int rt, int l, int r, int L, int R , int val) {
  if(L <= l && R >= r) {
    lazy[rt] = val;
    T[rt] = val;
    return ;
  }
  down(rt);
  int mid = l + r >> 1;
  if(mid >= L) upd(lson, L, R, val);
  if(mid < R) upd(rson, L, R, val);
} 
set<int> se;
void qry(int rt, int l, int r) {
  if(l == r) {
    if(T[rt])se.insert(T[rt]);
    return ;
  }
  down(rt);
  int mid = l + r >> 1;
  qry(lson); qry(rson);
}
int main() {
  int t; scanf("%d", &t);
  while(t--) {
    int n; scanf("%d", &n);
    ve.clear();
    for(int i = 0; i < n; ++i) scanf("%d %d", &e[i].l, &e[i].r), ve.push_back(e[i].l),ve.push_back(e[i].r);
    sort(ve.begin(), ve.end());
    ve.erase(unique(ve.begin(), ve.end()), ve.end());
    int len = ve.size();
    build(1, 1, len);
    for(int i = 1; i <= n; ++i) 
      upd(1,1,len,getid(e[i-1].l), getid(e[i-1].r), i);
    se.clear();
    qry(1, 1, len);
    printf("%d\n", se.size());
  }
	return 0;
}

Heavy Transportation

Heavy Transportation
最大生成樹，使1和n連通的那條邊

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<queue>
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const double Pi = acos(-1);
namespace io{
  template <typename T> inline void read(T &x) {
    x = 0; T f = 1;char s = getchar();
    for(; !isdigit(s); s = getchar()) if(s == '-') f = -1;
    for(;  isdigit(s); s = getchar()) x = (x << 3) + (x << 1) + (s ^ 48);
    x *= f;
  }
  template <typename T> inline void write(T x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x/10);
    putchar(x%10+'0');
  }
};
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _for(n,m,i) for (register int i = (n); i <  (m); ++i)
#define _rep(n,m,i) for (register int i = (n); i <= (m); ++i)
#define _srep(n,m,i)for (register int i = (n); i >= (m); i--)
#define _sfor(n,m,i)for (register int i = (n); i >  (m); i--)
#define ef(u, i) for(int i = head[u]; i; i = e[i].next)
#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
#define lowbit(x) x & (-x)
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e5+5;
struct node {
  int u, v, w;
  bool operator < (const node &a) const {
    return w > a.w;
  }
}e[N];
int f[N];
int Find(int x) {
  return x == f[x] ? x : f[x] = Find(f[x]);
}
int main() {
  int t; scanf("%d", &t);
  for(int ca = 1; ca <= t; ++ca) {
    int n, m; scanf("%d %d", &n, &m);
    
    for(int i = 1; i <= n; ++i) f[i] = i;
    
    for(int i = 0; i < m; ++i) {
      scanf("%d %d %d", &e[i].u, &e[i].v, &e[i].w);
    }
    sort(e, e + m);
    int w;
    
    for(int i = 0; i < m; ++i) {
      int fx = Find(e[i].u), fy = Find(e[i].v);
      if(fx != fy) {
        f[fx] = fy;
        w = e[i].w;
      }
      if(Find(1) == Find(n)) break;
    }
    printf("Scenario #%d:\n%d\n\n", ca, w);
  }  
	return 0;
}

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