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| 1 | +#include <bits/stdc++.h> |
| 2 | +using namespace std; |
| 3 | + |
| 4 | +// Type definitions |
| 5 | +typedef long long ll; |
| 6 | +typedef pair<int, int> pii; |
| 7 | +typedef pair<ll, ll> pll; |
| 8 | +typedef vector<int> vi; |
| 9 | +typedef vector<ll> vl; |
| 10 | +typedef vector<pii> vpii; |
| 11 | +typedef vector<pll> vpll; |
| 12 | +typedef vector<vi> vvi; |
| 13 | +typedef vector<vl> vvl; |
| 14 | + |
| 15 | +// Macros |
| 16 | +#define nline "\n" |
| 17 | +#define all(x) (x).begin(), (x).end() |
| 18 | +#define rall(x) (x).rbegin(), (x).rend() |
| 19 | +#define sz(x) (int)(x).size() |
| 20 | +#define pb push_back |
| 21 | +#define mp make_pair |
| 22 | +#define F first |
| 23 | +#define S second |
| 24 | +#define forn(i, n) for (int i = 0; i < int(n); i++) |
| 25 | +#define forr(i, a, b) for (int i = a; i <= b; i++) |
| 26 | +#define ford(i, a, b) for (int i = a; i >= b; i--) |
| 27 | +#define elasped_time 1.0 * clock() / CLOCKS_PER_SEC |
| 28 | + |
| 29 | +// Constants |
| 30 | +const int MOD = 1e9 + 7; |
| 31 | +const ll INF = 1e18; |
| 32 | +const double EPS = 1e-9; |
| 33 | +const double PI = acos(-1); |
| 34 | + |
| 35 | +ll mod_add(ll a, ll b, ll m = MOD) { return ((a % m) + (b % m)) % m; } |
| 36 | +ll mod_sub(ll a, ll b, ll m = MOD) { return ((a % m) - (b % m) + m) % m; } |
| 37 | +ll mod_mul(ll a, ll b, ll m = MOD) { return ((a % m) * (b % m)) % m; } |
| 38 | + |
| 39 | +ll mod_pow(ll base, ll exp, ll m = MOD) |
| 40 | +{ |
| 41 | + ll res = 1; |
| 42 | + base %= m; |
| 43 | + while (exp > 0) |
| 44 | + { |
| 45 | + if (exp & 1) |
| 46 | + res = mod_mul(res, base, m); |
| 47 | + base = mod_mul(base, base, m); |
| 48 | + exp >>= 1; |
| 49 | + } |
| 50 | + return res; |
| 51 | +} |
| 52 | + |
| 53 | +ll mod_inv(ll a, ll m = MOD) |
| 54 | +{ |
| 55 | + return mod_pow(a, m - 2, m); // Only works if m is prime |
| 56 | +} |
| 57 | + |
| 58 | +ll mod_div(ll a, ll b, ll m = MOD) |
| 59 | +{ |
| 60 | + return mod_mul(a, mod_inv(b, m), m); |
| 61 | +} |
| 62 | + |
| 63 | +// Binary exponentiation (for non-modular calculations) |
| 64 | +ll binpow(ll base, ll exp) |
| 65 | +{ |
| 66 | + ll res = 1; |
| 67 | + while (exp > 0) |
| 68 | + { |
| 69 | + if (exp & 1) |
| 70 | + res *= base; |
| 71 | + base *= base; |
| 72 | + exp >>= 1; |
| 73 | + } |
| 74 | + return res; |
| 75 | +} |
| 76 | + |
| 77 | +/************/ |
| 78 | +void solve() |
| 79 | +{ |
| 80 | + int n, k; |
| 81 | + cin >> n >> k; |
| 82 | + |
| 83 | + string str; |
| 84 | + cin >> str; |
| 85 | + |
| 86 | + string rev = str; |
| 87 | + reverse(all(rev)); |
| 88 | + |
| 89 | + if (str < rev) |
| 90 | + cout << "YES" << nline; |
| 91 | + else if (count(all(str), str[0]) == n) |
| 92 | + cout << "NO" << nline; |
| 93 | + else if (k) |
| 94 | + cout << "YES" << nline; |
| 95 | + else |
| 96 | + cout << "NO" << nline; |
| 97 | +} |
| 98 | +int main() |
| 99 | +{ |
| 100 | + ios_base::sync_with_stdio(0); |
| 101 | + cin.tie(0); |
| 102 | + cout.tie(0); |
| 103 | + |
| 104 | +#ifndef ONLINE_JUDGE |
| 105 | + freopen("./outputs/input.txt", "r", stdin); |
| 106 | + freopen("./outputs/output.txt", "w", stdout); |
| 107 | +#endif |
| 108 | + |
| 109 | + int t; |
| 110 | + cin >> t; |
| 111 | + while (t--) |
| 112 | + solve(); |
| 113 | + |
| 114 | + return 0; |
| 115 | +} |
| 116 | +// Explanatie |
| 117 | +/* */ |
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