Some minor changes

Author: Mehran

handy-algorithms/fastPow.c

@@ -5,16 +5,9 @@
 
 
 ll pw(ll a, ll b) {
- if (b == 0) {
- return 1;
- }
-
+ if (b == 0) return 1;
  ll v = pw(a, b / 2);
- v = (v * v) % MOD;
-
- if (b & 1) {
- v = (v * a) % MOD;
- }
-
+ v = (v * v) % mod;
+ if (b & 1) v = (v * a) % mod;
  return v;
 }

string-processing/z.cpp

@@ -1,19 +1,10 @@
-// z function returns an array of size |s| which i'th number shows size of longest prefix of t starting from this index of s
-// O(|s| + |t|)
-
-// t is the pattern you are looking for in s
-vi zf(string s, string t) {
- int n = s.size(), m = t.size();
- s = t + '#' + s;
- vi z(n + m + 1);
- int l = 0, r = 1;
- for (int i = 1; i <= n + m; i++) {
- if (i < r) z[i] = min(z[i - l], r - i);
- while (i + z[i] <= n + m && s[i + z[i]] == s[z[i]]) z[i]++;
- if (i + z[i] > r)
- tie(l, r) = ii(i, i + z[i]);
+vi z_function(string s) {
+ int n = s.size();
+ vi z(n);
+ for (int i = 1, l = 0, r = 0; i < n; ++i) {
+ if (i <= r) z[i] = min (r - i + 1, z[i - l]);
+ while (i + z[i] < n && s[z[i]] == s[i + z[i]]) ++z[i];
+ if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1;
  }
- vi ret_z(n);
- forn(i, n) ret_z[i] = z[i + m + 1];
- return ret_z;
+ return z;
 }

template.cpp

@@ -25,6 +25,7 @@ typedef vector<vii> vvii;
 #define all(a) (a).begin(), (a).end()
 #define inf 1000000000
 #define eps 1e-9
+mt19937 rng32(chrono::steady_clock::now().time_since_epoch().count());
 
 int main() {
  ios::sync_with_stdio(0);