COCI 2015、2016 1st round 题解（官方）

官方题解：

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官方代码：

Code-KARTE:

#include <cstdio>
#include <iostream>
#include <cstring>

using namespace std;

const int MAXB = 5;
const int MAXN = 20;

bool bio[MAXB][MAXN];

int getColor(char chr) {
  if (chr == 'P') return 0;
  if (chr == 'K') return 1;
  if (chr == 'H') return 2;
  if (chr == 'T') return 3;
}

int main(void) {
  string s;
  cin >> s;
  for (int i = 0; i < s.size(); i += 3) {
    int b = getColor(s[i]);
    int x = (s[i + 1] - '0') * 10 + s[i + 2] - '0';
    if (bio[b][x]) {
      printf("GRESKA\n");
      return 0;
    }
    bio[b][x] = true;
  }

  for (int i = 0; i < 4; ++i) {
    int cnt = 0;
    for (int j = 1; j <= 13; ++j)
      if (bio[i][j])
	++cnt;
    printf("%d ",13 - cnt);
  }
  printf("\n");
    
  return 0;
}

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Code-AKCIJA:

#include <cstdio>
#include <algorithm>
using namespace std;

#define MAXN 100000
typedef long long llint;

int C[MAXN];

bool cmp(int a, int b) {
  return a > b;
}

int main(void) {
  int n; scanf ("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf ("%d", &C[i]);
  }

  sort(C, C+n, cmp);

  llint sol = 0;
  for (int i = 0; i < n; i++) {
    if (i % 3 == 2) {
      continue;
    }
    sol += C[i];
  }

  printf ("%lld\n", sol);

  return 0;
}

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Code-BALONI:

#include <cstdio>
#include <algorithm>
#include <cstring>
#include <set>

using namespace std;

const int MAXN = 1 << 20;

int n;

set <int> S[MAXN];
int find (int pos, int v) {
  set<int>::iterator it = S[v].lower_bound(pos);
  if (it == S[v].end()) return -1;
  return *it;
}

int v[MAXN];

int main (void){
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    scanf("%d", &v[i]);
    S[v[i]].insert(i);
  }

  int ans = 0;
  for (int i = 0; i < n; ++i) {
   if (S[v[i]].count(i) == 0) continue;
   int pos = i;
   ++ans;
   while (pos >= 0) {
      S[v[pos]].erase(pos);
      pos = find(pos, v[pos] - 1);
   }
  }

  printf("%d\n", ans);

  return 0;
}

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Code-TOPOVI:

#include <cstdio>
#include <iostream>
#include <map>

using namespace std;

int n, k, q;
long long sol;
map <int, int> rcnt, ccnt;
map <int, int> rxor, cxor;
map <pair<int, int>, int> rook;

void moveRook(int r, int c, int val) {
  sol -= n - ccnt[rxor[r]];
  sol -= n - rcnt[cxor[c]];
  if (rxor[r] != cxor[c])
    sol += 1;

  --rcnt[rxor[r]];
  rxor[r] ^= val;
  ++rcnt[rxor[r]];

  --ccnt[cxor[c]];
  cxor[c] ^= val;
  ++ccnt[cxor[c]];

  sol += n - ccnt[rxor[r]];
  sol += n - rcnt[cxor[c]];
  if (rxor[r] != cxor[c])
    sol -= 1;

  rook[make_pair(r, c)] ^= val;
}

void init(void) {
  scanf("%d %d %d",&n,&k,&q);
  rcnt[0] = ccnt[0] = n;
  for (int i = 0; i < k; ++i) {
    int r, c, val;
    scanf("%d %d %d",&r,&c,&val);
    --r;
    --c;
    moveRook(r, c, val);
  }
}

void solve(void) {
  while (q-- > 0) {
    int r1, c1, r2, c2;
    scanf("%d %d %d %d",&r1,&c1,&r2,&c2);
    --r1; --c1;
    --r2; --c2;
    int rookValue = rook[make_pair(r1, c1)];
    moveRook(r1, c1, rookValue);
    moveRook(r2, c2, rookValue);
    printf("%lld\n",sol);
  }
}

int main(void) {
  init();
  solve();
  return 0;
}

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Code-RELATIVNOST:

#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>

using namespace std;

typedef unsigned int uint;

const int MAXN = 100005;
const int MAXC = 21;
const int mod = 10007;

int n, c, q;
int a[MAXN];
int b[MAXN];
int T[2 * MAXN][MAXC];

void update(int x) {
  for (int i = 0; i <= c; ++i) T[x][i] = 0;

  for (int i = 0; i <= c; ++i)
    for (int j = 0; j <= c; ++j)
      T[x][min(i + j, c)] += (T[x * 2][i] * T[x * 2 + 1][j]) % mod;

  for (int i = 0; i <= c; ++i) T[x][i] %= mod;
}

void change(int x) {
  x += n;
  memset(T[x], 0, sizeof T[x]);
  T[x][1] = a[x - n] % mod;
  T[x][0] = b[x - n] % mod;

  for (x /= 2; x > 0; x /= 2) update(x);
}

int main(void) {
  scanf("%d%d", &n, &c);
  for (int i = 0; i < n; ++i) scanf("%d", &a[i]);
  for (int i = 0; i < n; ++i) scanf("%d", &b[i]);
  for (int i = 0; i < n; ++i) {
    T[i + n][0] = b[i] % mod;
    T[i + n][1] = a[i] % mod;
  }

  for (int i = n-1; i >= 1; --i)
    update(i);

  scanf("%d", &q);
  for (int i = 0; i < q; ++i) {
    int p;
    scanf("%d", &p); --p;
    scanf("%d%d", &a[p], &b[p]); 
    change(p);
    printf("%d\n", T[1][c]);
  }

  return 0;
}

---

Code-UZASTOPNI:

#include <cstdio>
#include <iostream>
#include <cstring>
#include <bitset>
#include <vector>

#define lo first
#define hi second

using namespace std;

using interval = pair<int, int>;

const int MAXN = 10010;
const int MAXK = 110;

int n, v[MAXN];
vector<int> e[MAXN];

vector<interval> s[MAXN];
vector<int> q[MAXK];
bitset<MAXK> flag[MAXN][MAXK];

void dfs(int x) {
  for (auto y : e[x]) 
    dfs(y);

  for (int i = 0; i < MAXK; ++i)
    q[i].clear();
  for (auto y : e[x]) {
    for (auto it : s[y])
      q[it.lo].push_back(it.hi);
  }
  
  for (int lo = MAXK - 1; lo >= 1; --lo) {
    if (lo == v[x]) {
      flag[x][lo] |= flag[x][lo + 1];
      flag[x][lo].set(lo);
    } else {
      for (auto hi : q[lo]) {
      	if (hi < v[x] || lo > v[x]) {
      	  flag[x][lo] |= flag[x][hi + 1];
      	  flag[x][lo].set(hi);
      	}
      }
    }

    for (int hi = MAXK - 1; hi >= lo; --hi)
      if (flag[x][lo].test(hi) && v[x] >= lo && v[x] <= hi) {
    	s[x].emplace_back(lo, hi);
      }
  }
}

void init(void) {
  scanf("%d",&n);
  for (int i = 0; i < n; ++i)
    scanf("%d",&v[i]);
  for (int i = 0; i < n - 1; ++i) {
    int a, b;
    scanf("%d %d",&a,&b);
    --a;
    --b;
    e[a].push_back(b);
  }
}

void solve(void) {
  dfs(0);
  printf("%d\n",s[0].size());
}

int main(void) {
  init();
  solve();
  return 0;
}