#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, k; cin >> n >> k;
vector<vector<vector<ll>>> dp(n, vector<vector<ll>>(n, vector<ll>(n+1, 0)));
str s; cin >> s;
for(int i = 0; i < n; i++){
if(s[i] == 'C' && n%2 == 1) for(int kk = 0; kk <= n; kk++) dp[i][i][kk] = 1;
}
for(int sz = 2; sz <= n; sz++) for(int i = 0, j = sz-1; j < n; i++, j++){
for(int kk = 0; kk <= n; kk++){
if(kk != 0) dp[i][j][kk] = dp[i][j][kk-1];
if(s[i] == 'C' && s[j] == 'C'){
if((n-sz)%2 == 0){
ll cur = 0;
if(kk != 0) cur = max(dp[i+1][j][kk-1], dp[i][j-1][kk-1]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
else{
ll cur = min(dp[i+1][j][kk], dp[i][j-1][kk])+1;
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
}
else if(s[i] == 'C'){
if((n-sz)%2 == 0){
ll cur = dp[i][j-1][kk];
if(kk != 0) cur = max(cur, dp[i+1][j][kk-1]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
else{
ll cur = min(dp[i+1][j][kk]+1, dp[i][j-1][kk]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
}
else if(s[j] == 'C'){
if((n-sz)%2 == 0){
ll cur = dp[i+1][j][kk];
if(kk != 0) cur = max(cur, dp[i][j-1][kk-1]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
else{
ll cur = min(dp[i+1][j][kk], dp[i][j-1][kk]+1);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
}
else{
if((n-sz)%2 == 0){
ll cur = max(dp[i+1][j][kk], dp[i][j-1][kk]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
else{
ll cur = min(dp[i+1][j][kk], dp[i][j-1][kk]);
dp[i][j][kk] = max(dp[i][j][kk], cur);
}
}
}
}
cout << (dp[0][n-1][k-1] >= k ? "DA\n":"NE\n");
}
