Russian Code Cup 2017 Third Qualification Round

Author: wiwitrifai

russiancc/2017_qual3/a.cpp

@@ -0,0 +1,23 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main() {
+  int t;
+  scanf("%d", &t);
+  while (t--) {
+    long long n;
+    cin >> n;
+    int dig = 1;
+    long long cnt = 26;
+    while (cnt < n) n -= cnt, dig++, cnt *= 26;
+    for (int i = 0; i < dig; i++) {
+      cnt /= 26;
+      int now = 0;
+      while (n > cnt) now++, n -= cnt;
+      printf("%c", now + 'A');
+    }
+    printf("\n");
+  }
+  return 0;
+}

russiancc/2017_qual3/b.cpp

@@ -0,0 +1,45 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+const int N = 1e5 + 5;
+pair<long long, long long> hr[N];
+long long h, a;
+bool cmp(pair<long long, long long> le, pair<long long, long long> ri) {
+  return le.second * ((le.first + a - 1)/a) > ri.second * ((ri.first + a - 1)/a);
+}
+long long win[N];
+
+int main() {
+  int t;
+  scanf("%d", &t);
+  while (t--) {
+    int n;
+    scanf("%d %lld %lld", &n, &h, &a);
+    for (int i = 0; i < n; ++i) {
+      scanf("%lld %lld", &hr[i].first, &hr[i].second);
+    }
+    sort(hr, hr+n, cmp);
+    long long now = 0;
+    for (int i = n-1; i >= 0; i--) {
+      int rec = (hr[i].first + a - 1)/a - 1;
+      now = max(now, hr[i].second * rec);
+      win[i] = now;
+    }
+    int ans = 0;
+    for (int i = 0; i < n; i++) {
+      if (h <= win[i]) break;
+      long long rec = (hr[i].first + a - 1)/a;
+      long long aa = hr[i].second;
+      long long w = (h + aa - 1) / aa;
+      if (w <= rec)
+        break;
+      h -= aa * rec;
+      ans++;
+    }
+    if (ans >= n)
+      ans = -1;
+    printf("%d\n", ans);
+  }
+  return 0;
+}

russiancc/2017_qual3/c.cpp

@@ -0,0 +1,30 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+long long get(long long r) {
+  if (r < 10) return r;
+  long long ans = 9, mul = 10;
+  while (mul + 1 <= r) {
+    for (int i = 1; i <= 9; ++i) {
+      if (r < (mul+1) * i) break;
+      long long v = r - (mul+1) * i;
+      v /= 10;
+      ans += min(v+1, mul/10);
+    }
+    mul *= 10;
+  }
+  return ans;
+}
+
+int main() {
+  int t;
+  scanf("%d", &t);
+  while (t--) {
+    long long l, r;
+    scanf("%lld %lld", &l, &r);
+    l--;
+    printf("%lld\n", get(r) - get(l));
+  }
+  return 0;
+}

russiancc/2017_qual3/d.cpp

@@ -0,0 +1,99 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+
+const int N = 1e5 + 5, mod = 1e9 + 7;
+
+long long C[22][22];
+
+struct poly {
+  int n;
+  int x[22];
+  poly(int n = 0) : n(n) {
+    memset(x, 0, sizeof x);
+  }
+  void reset(int n = 0) {
+    this->n = n;
+    memset(x, 0, sizeof x);
+  }
+  long long get(long long p) {
+    long long ret = 0, now = 1;
+    for (int i = 0; i <= n; i++) {
+      ret = (ret + 1LL * x[i] * now) % mod;
+      now = now * p % mod;
+    }
+    return ret;
+  }
+  void add(poly & other) {
+    for (int i = 0; i <= n; i++) {
+      x[i] += other.x[i];
+      if (x[i] >= mod) x[i] -= mod;
+    }
+  }
+};
+
+poly val[N], up[N];
+long long ans[N];
+int n, lv[N], k;
+vector< int > g[N];
+
+void dfs(int v, int par = -1) {
+  if (par != -1)
+    val[v].add(val[par]);
+  for (int u : g[v]) {
+    lv[u] = lv[v] + 1;
+    dfs(u, v);
+    up[v].add(up[u]);
+  }
+}
+
+int main() {
+  int t;
+  scanf("%d", &t);
+  while (t--) {
+    int r = -1;
+    scanf("%d %d", &n, &k);
+    for (int i = 0; i < n; i++) g[i].clear();
+    for (int i = 0; i < n; i++) {
+      int p;
+      scanf("%d", &p); p--;
+      if (p < 0)
+        r = i;
+      else
+        g[p].push_back(i);
+      val[i].reset(k);
+      up[i].reset(k);
+    }
+    int q;
+    scanf("%d", &q);
+    for (int i = 0; i < q; i++) {
+      int y, z, x;
+      scanf("%d %d", &y, &z);
+      z--;
+      if (y == 2) {
+        for (int j = 0; j <= k; j++) {
+          scanf("%d", &x);
+          up[z].x[j] += x;
+          if (up[z].x[j] >= mod)
+            up[z].x[j] -= mod;
+        }
+      }
+      else {
+        for (int j = 0; j <= k; j++) {
+          scanf("%d", &x);
+          val[z].x[j] += x;
+          if (val[z].x[j] >= mod)
+            val[z].x[j] -= mod;
+        }
+      }
+    }
+    lv[r] = 1;
+    dfs(r);
+    for (int i = 0; i < n; i++)
+      ans[i] = (up[i].get(lv[i]) + val[i].get(lv[i])) % mod;
+    for (int i = 0; i < n; i++) printf("%d ", ans[i]);
+    printf("\n");
+  }
+  return 0;
+}