UVa 1519 Dictionary Size

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <algorithm>
  4 #include <iostream>
  5 #include <string>
  6 #include <vector>
  7 #include <stack>
  8 #include <bitset>
  9 #include <cstdlib>
 10 #include <cmath>
 11 #include <set>
 12 #include <list>
 13 #include <deque>
 14 #include <map>
 15 #include <queue>
 16 #include <fstream>
 17 #include <cassert>
 18 #include <unordered_map>
 19 #include <unordered_set>
 20 #include <cmath>
 21 #include <sstream>
 22 #include <time.h>
 23 #include <complex>
 24 #include <iomanip>
 25 #define Max(a,b) ((a)>(b)?(a):(b))
 26 #define Min(a,b) ((a)<(b)?(a):(b))
 27 #define FOR(a,b,c) for (ll (a)=(b);(a)<(c);++(a))
 28 #define FORN(a,b,c) for (ll (a)=(b);(a)<=(c);++(a))
 29 #define DFOR(a,b,c) for (ll (a)=(b);(a)>=(c);--(a))
 30 #define FORSQ(a,b,c) for (ll (a)=(b);(a)*(a)<=(c);++(a))
 31 #define FORC(a,b,c) for (char (a)=(b);(a)<=(c);++(a))
 32 #define FOREACH(a,b) for (auto &(a) : (b))
 33 #define rep(i,n) FOR(i,0,n)
 34 #define repn(i,n) FORN(i,1,n)
 35 #define drep(i,n) DFOR(i,n-1,0)
 36 #define drepn(i,n) DFOR(i,n,1)
 37 #define MAX(a,b) a = Max(a,b)
 38 #define MIN(a,b) a = Min(a,b)
 39 #define SQR(x) ((LL)(x) * (x))
 40 #define Reset(a,b) memset(a,b,sizeof(a))
 41 #define fi first
 42 #define se second
 43 #define mp make_pair
 44 #define pb push_back
 45 #define all(v) v.begin(),v.end()
 46 #define ALLA(arr,sz) arr,arr+sz
 47 #define SIZE(v) (int)v.size()
 48 #define SORT(v) sort(all(v))
 49 #define REVERSE(v) reverse(ALL(v))
 50 #define SORTA(arr,sz) sort(ALLA(arr,sz))
 51 #define REVERSEA(arr,sz) reverse(ALLA(arr,sz))
 52 #define PERMUTE next_permutation
 53 #define TC(t) while(t--)
 54 #define forever for(;;)
 55 #define PINF 1000000000000
 56 #define newline ‘\n‘
 57 
 58 #define test if(1)if(0)cerr
 59 using namespace std;
 60 using namespace std;
 61 typedef vector<int> vi;
 62 typedef vector<vi> vvi;
 63 typedef pair<int,int> ii;
 64 typedef pair<double,double> dd;
 65 typedef pair<char,char> cc;
 66 typedef vector<ii> vii;
 67 typedef long long ll;
 68 typedef unsigned long long ull;
 69 typedef pair<ll, ll> l4;
 70 const double pi = acos(-1.0);
 71 
 72 const int maxnode = 4e5+5, sigma_size = 26;
 73 struct Trie
 74 {
 75     int g[maxnode][sigma_size], sz;
 76     int cnt[sigma_size];
 77     void init()
 78     {
 79         sz = 1; Reset(g[0], 0);
 80         Reset(cnt, 0);
 81     }
 82     int idx(char c)
 83     {
 84         return c - ‘a‘;
 85     }
 86     void insert(const string &str)
 87     {
 88         int u = 0, n = str.length();
 89         rep(i, n)
 90         {
 91             int c = idx(str[i]);
 92 
 93             if (!g[u][c])
 94             {
 95                 Reset(g[sz], 0);
 96                 g[u][c] = sz++;
 97                 if (i)  cnt[c] += 1;
 98             }
 99             u = g[u][c];
100         }
101     }
102 };
103 Trie prefix, suffix;
104 bitset<sigma_size> vis;
105 int n;
106 
107 int main()
108 {
109     
110     ios::sync_with_stdio(false);
111     cin.tie(0);
112     while (cin >> n)
113     {
114         string line;
115         prefix.init(), suffix.init();
116         vis.reset();
117         rep(i, n)
118         {
119             cin >> line;
120             if (line.length() == 1) vis[line[0]-‘a‘] = true;
121             prefix.insert(line);
122             reverse(line.begin(), line.end());
123             suffix.insert(line);
124         }
125         ll ans = (ll) (prefix.sz-1) * (suffix.sz-1);
126         rep(i, sigma_size)
127         {
128             ans -= (ll) prefix.cnt[i] * suffix.cnt[i] - vis[i];
129         }
130         
131         cout << ans << newline;
132     }
133     
134     
135     
136 
137 
138 }