Merge branch 'master' of https://github.com/fsq/codeforces

Author: fsq

1151.E. Number of Components.cpp

@@ -0,0 +1,78 @@
+#include <cstdio>
+#include <iostream>
+#include <cstring>
+#include <cmath>
+#include <ctime>
+#include <vector>
+#include <string>
+#include <algorithm>
+#include <map>
+#include <set>
+#include <unordered_map>
+#include <unordered_set>
+#include <queue>
+#include <deque>
+#include <stack>
+#include <numeric>
+#include <memory>
+#include <list>
+#include <climits>
+#include <fstream>
+#include <sstream>
+#include <random>
+#include <functional>
+
+#define PB                  push_back
+#define F                   first
+#define S                   second
+
+#define REP(i,from,to)      for(auto i=(from); i<=(to); ++i)
+#define PER(i,from,to)      for(auto i=(from); i>=(to); --i)
+#define REP_IF(i,from,to,assert)   for(auto i=(from); i<=(to); ++i) if (assert)
+
+#define FOR(i,less_than)    for (auto i=0; i<(less_than); ++i)
+#define FORI(i, container)  for (auto i=0; i<(container).size(); ++i)
+#define FORI_IF(i, container, assert) for (auto i=0; i<(container).size(); ++i) if (assert)
+#define ROFI(i, container)  for (auto i=SZ(container)-1; i>=0; --i)
+#define FOREACH(elem, container)  for (auto elem : (container))
+#define FOREACH_IF(elem, container, assert) for (auto elem : (container)) if (assert)
+
+#define MEMSET(container, value)  memset(container, value, sizeof(container))
+#define MEMSET0(container)        memset(container, 0, sizeof(container))
+#define FILL(container, value)    fill(container.begin(), container.end(), value)
+#define FILL0(container)    fill(container.begin(), container.end(), 0)
+#define ALL(container)            (container).begin(), (container).end()
+#define SZ(container)             (int)((container).size())
+
+#define BACK(set_map)       *prev((set_map).end(), 1)
+#define FRONT(set_map)      *(set_map).begin()
+
+#define POP(var, container) auto var=(container.front()); container.pop();
+
+using PII = std::pair<int,int>;
+using LL  = long long;
+using VI  = std::vector<int>;
+using CVI = const VI;
+using VLL = std::vector<LL>;
+using VVI = std::vector<VI>;
+using VVLL = std::vector<VLL>;
+
+using namespace std;
+
+int main() {
+  ios::sync_with_stdio(false);
+  int n;
+  cin >> n;
+  VLL a(n+1), f(n+1);
+  a[0] = n + 1;
+  REP(i, 1, n) {
+    cin >> a[i];
+    f[i] = f[i-1];
+    if (a[i] > a[i-1]) 
+      f[i] += (a[i]-a[i-1]) * (n-a[i]+1);
+    else if (a[i] < a[i-1])
+      f[i] += a[i] * (a[i-1]-a[i]);
+  }
+  cout << f[n] << endl;
+  return 0;
+}