/*
* * author: attacker
* * created: 01.03.2026 11:38:36
*/
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "algo/debug.h"
#else
#define debug(...) 42
#endif
#define mt_rng mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n, k;
string s;
cin >> n >> k >> s;
bool fail = false;
auto Solve = [&](auto&& self, int low, int high, int cc_1, int cc_2, bool which) {
if (high < low) {
return;
}
if (cc_1 == k) {
fail = true;
return;
}
if (which) {
if (s[low] == s[high]) {
self(self, low + 1, high, cc_1 += (s[low] == 'C'), cc_2, !which);
self(self, low, high - 1, cc_1 += (s[high] == 'C'), cc_2, !which);
} else if (s[low] == 'C') {
self(self, low, high - 1, cc_1 += (s[high] == 'C'), cc_2, !which);
} else {
self(self, low + 1, high, cc_1 += (s[low] == 'C'), cc_2, !which);
}
} else {
self(self, low + 1, high, cc_1, cc_2 += (s[low] == 'C'), !which);
self(self, low, high - 1, cc_1, cc_2 += (s[high] == 'C'), !which);
}
return;
};
Solve(Solve, 0, n - 1, 0, 0, true);
cout << (fail ? "NE" : "DA") << '\n';
return 0;
}
