Submission #297542

#	Time	Username	Problem	Language	Result	Execution time	Memory
297542		Hehehe	Mate (COCI18_mate)	C++14	0 / 100	2040 ms	49716 KiB

mate

#include<bits/stdc++.h> //:3
using namespace std;
#define DIM 2010
#define MOD 1000000007


//ifstream cin ("date.in");
//ofstream cout ("date.out");
int v[DIM],c[DIM][DIM],f[DIM],dp[DIM][30][30],a[DIM][30];
char l1,l2;
string s;
int n,i,j,x,y,q,lg;
int main (){

    cin >> s;
    n = s.size();
    s = '.' + s;

    for (i=1;i<=n;i++)
        v[i] = s[i] - 'a' + 1;

    c[0][0] = 1;

    for (i=1;i<=n;i++){
        c[i][0] = 1;
        for (j=1;j<=i;j++){
            c[i][j] = c[i-1][j-1] + c[i-1][j];
            if (c[i][j] >= MOD)
                c[i][j] -= MOD;
        }}




    for (i=1;i<=n;i++)
        for (j=i+1;j<=n;j++)
            a[i][v[j]]++;

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            cout << c[i][j] << ' ';
        }cout << '\n';
    }
    
    for (lg=2;lg<=n;lg++){
        for (i=lg-1;i<=n;i++){
            x = v[i];
            for (y=1;y<=26;y++){
                dp[lg][x][y] = dp[lg][x][y]+1LL*a[i][y]*c[i-1][lg-2]%MOD;
                if (dp[lg][x][y] >= MOD)
                    dp[lg][x][y] -= MOD;
            }}}


    cin >> q;
    for (;q--;){
        cin >> lg >> l1 >> l2;
        cout << dp[lg][l1-'a'+1][l2-'a'+1] << '\n';
    }


    return 0;
}

• Subtask 1: 0 / 100