Cod sursa(job #2382551)

Utilizator mariusn01Marius Nicoli mariusn01 Data 18 martie 2019 14:27:13
Problema Lista lui Andrei Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.16 kb
#include<fstream>
#define MOD 104659
using namespace std;
char x, y;

int a[26][26];

int D[1001][26];
/// D[i][j] = CATE siruri de lungime i se termina cu a j-a litera
int n, m, i, j, k;
int sol;

int main(){

    ifstream fin ("nrcuv.in");
    ofstream fout("nrcuv.out");

    fin>>n>>m;
    for (i=1;i<=m;i++) {
        fin>>x>>y;
        a[ x-'a' ][ y-'a' ] = 1;
        a[ y-'a' ][ x-'a' ] = 1;
    }

    for (i=0;i<26;i++)
        D[1][i] = 1;

    for (i=2;i<=n;i++) {
        /// calculez nmar de siruri de lungime i
        for (j=0;j<26;j++) {
            /// calculez D[i][j] adica, cate siruri de lungime i terminate cu litera j
            /// adaug litera j la finalul unui sir de lungime i-1
            D[i][j] = 0;
            /// caut sa pun litera j dupa fiecare litera acceptabila a unui sir de lungime i-1

            for (k=0;k<26;k++)
                if (a[ k ][ j ] == 0) {
                    D[i][j] += D[i-1][k];
                    D[i][j] %= MOD;
                }
        }
    }

    sol = 0;
    for (i=0;i<26;i++) {
        sol += D[n][i];
        sol %= MOD;
    }

    fout<<sol;

    return 0;

}