CodeForce 常用模板
作者：互联网
目录
代码模板
#include <bits/stdc++.h>
using namespace std;
#define DEBUG 0
// #define int long long
#define fi first
#define se second
#define pb push_back
#define vt std::vector
#define lb lower_bound
#define eb emplace_back
#define sz(x) (int(x.size()))
#define all(x) x.begin(), x.end()
#define mst(x, bit) memset(x, bit, sizeof(x))
#define rep(i, l, r) for (ll i = (l); i < (r); ++ i)
#define per(i, l, r) for (ll i = (l); i >= (r); -- i)
#define dmp(x) cerr << __LINE__ << "->" << #x << " " << x << "\n"
using db = double;
using ll = long long;
using pdd = pair<db, db>;
using pll = pair<ll, ll>;
using pii = pair<int, int>;
template<typename... Args>
inline void read(Args&... args) { }
template<typename T, typename... Args>
inline void read(T &val, Args&... args) { std::cin >> val; read(args...); }
template<typename... Args>
inline void _wpr_(Args... args) { std::cout << '\n'; }
template<typename T, typename... Args>
inline void _wpr_(T val, Args... args) { std::cout << " " << val; _wpr_(args...); }
template<typename T, typename... Args>
void wpr(T val, Args... args) { std::cout << val; _wpr_(args...); }
const int mod = 1e9 + 7;
const int inf = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3f;
const int maxn = 1e5 + 50;
void solve(){
}
signed main(){
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
int t = 1;
// std::cin >> t;
while (t--) solve();
return 0;
}
KMP
#include <bits/stdc++.h>
using namespace std;
#define show(x) for (auto &e: x) cout << e << " "; cout << '\n';
struct KMP{
vector<int> next; // 失配时，模式串 pattern 跳转的位置
void build(const string &pattern){
int n = pattern.length();
next.resize(n + 1); // n + 1 可以保证再完成匹配后继续跳转的方便性（也可以快速获取整个字符串的最大前缀后缀匹配）
for (int i = 0, j = next[0] = -1; i < n; next[++i] = ++j){ // next[i + 1] = j + 1 往后推一位
while (~j && pattern[i] != pattern[j]) j = next[j];
}
}
vector<int> match(const string &pattern, const string &text){
build(pattern); // 预处理 next 数组
vector<int> res; // 代表文本串中所有匹配位置的开始
int n = pattern.length(), m = text.length();
for (int i = 0, j = 0; i < m; ++ i){
while (j > 0 && pattern[j] != text[i]) j = next[j]; // 当 j != 0 时用next数组不断尝试匹配
if (pattern[j] == text[i]) ++ j;
if (j == n) res.emplace_back(i - n + 1), j = next[j]; // 匹配成功，假如首位置，利用next多处理出的一位进行转移
}
return res;
}
};
int main(){
string ss = "ABABAB";
KMP kmp;
kmp.build(ss);
show(kmp.next)
return 0;
}
Prime
#include <bits/stdc++.h>
using namespace std;
namespace Prime{
const int Prime_max = 1e6 + 50;
int ptot; // tot prime
int prime[Prime_max / 10];
int is_prime[Prime_max + 1];
void getPrime(){
ptot = 0;
memset(is_prime, 0, sizeof(is_prime));
for (int i = 2; i <= Prime_max; ++ i){
if (!is_prime[i]) prime[ptot++] = i;
for (int j = 0; j < ptot && prime[j] <= Prime_max / i; ++ j){
is_prime[i * prime[j]] = 1;
if (i % prime[j] == 0) break; // i = k*prime[j], so i * prime[j+1] = (k*prime[j+1]) * prime[j]
}
}
}
vector<pair<int, int>> Factor(long long num){
vector<pair<int, int>> ret;
for (int i = 0; prime[i] <= num / prime[i]; ++ i){
pair<int, int> cur = {0, 0};
if (num % prime[i] == 0) {
cur.first = prime[i];
while (num % prime[i] == 0) ++ cur.second, num /= prime[i];
ret.push_back(cur);
}
}
if (num != 1) ret.push_back(make_pair(num, 1));
return ret;
}
void disp(vector<pair<int, int>> ftr){
std::cout << " show factor \n";
for (auto x: ftr)
std::cout << "Prime: " << setw(5) << x.first << " cnt: " << setw(5) << x.second << "\n";
std::cout << "---------------------\n";
}
}
signed main(){
using namespace Prime;
getPrime();
auto res = Factor(210);
disp(res);
return 0;
}
Random
#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#include <random>
#include <chrono>
// 获取a,b之间均匀分布的整数
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
// 茅台19937
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
ST Table
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 50;
const int logn = 21;
int n; // 长度
int st[maxn][logn]; // st(i, j) -> [i, i + 2^j - 1]
int Logn[maxn], arr[maxn];
inline void pre(){
Logn[1] = 0;
Logn[2] = 1;
for (int i = 3; i < maxn; ++ i) Logn[i] = Logn[i / 2] + 1;
}
void init(){
for (int i = 0; i < n; ++ i) st[i][0] = arr[i];
for (int j = 1; (1 << j) <= n; ++ j){
for (int i = 0; i + (1 << j) - 1 < n; ++ i){
st[i][j] = max(st[i][j - 1], st[i + (1 << (j - 1))][j - 1]);
}
}
}
int query(int l, int r){
int s = Logn[r - l + 1];
return max(st[l][s], st[r - (1 << s) + 1][s]);
}
INT128
#include <bits/stdc++.h>
using namespace std;
namespace I128{
#ifndef lll
#define lll __int128
#endif
lll read(){
lll x = 0, f = 1;
char ch = getchar();
while (ch < '0' || ch > '9') { if (ch == '-') f = -1; ch = getchar(); }
while (ch >= '0' && ch <= '9') { x = x * 10 + ch - '0'; ch = getchar(); }
return x * f;
}
void print(lll x){
if (x < 0) { putchar('-'); x = -x; }
if (x > 9) print(x / 10);
putchar(x % 10 + '0');
}
}
using namespace I128;
void solve(){
lll a = read();
print(a);
}
int main(){
// ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
int t = 1;
while (t--) solve();
return 0;
}
MINT/Combine
#include <bits/stdc++.h>
using namespace std;
template<int m>
struct modint{
unsigned int x;
constexpr modint()noexcept:x(){}
template<typename T>
constexpr modint(T x_)noexcept:x((x_%=m)<0?x_+m:x_){}
constexpr unsigned int val()const noexcept{return x;}
constexpr modint&operator++()noexcept{if(++x==m)x=0;return*this;}
constexpr modint&operator--()noexcept{if(x==0)x=m;--x;return*this;}
constexpr modint operator++(int)noexcept{modint res=*this;++*this;return res;}
constexpr modint operator--(int)noexcept{modint res=*this;--*this;return res;}
constexpr modint&operator+=(const modint&a)noexcept{x+=a.x;if(x>=m)x-=m;return*this;}
constexpr modint&operator-=(const modint&a)noexcept{if(x<a.x)x+=m;x-=a.x;return*this;}
constexpr modint&operator*=(const modint&a)noexcept{x=(unsigned long long)x*a.x%m;return*this;}
constexpr modint&operator/=(const modint&a)noexcept{return*this*=a.inv();}
constexpr modint operator+()const noexcept{return*this;}
constexpr modint operator-()const noexcept{return modint()-*this;}
constexpr modint pow(long long n)const noexcept
{
if(n<0)return pow(-n).inv();
modint x=*this,r=1;
for(;n;x*=x,n>>=1)if(n&1)r*=x;
return r;
}
constexpr modint inv()const noexcept
{
int s=x,t=m,x=1,u=0;
while(t)
{
int k=s/t;
s-=k*t;
swap(s,t);
x-=k*u;
swap(x,u);
}
return modint(x);
}
friend constexpr modint operator+(const modint&a,const modint&b){return modint(a)+=b;}
friend constexpr modint operator-(const modint&a,const modint&b){return modint(a)-=b;}
friend constexpr modint operator*(const modint&a,const modint&b){return modint(a)*=b;}
friend constexpr modint operator/(const modint&a,const modint&b){return modint(a)/=b;}
friend constexpr bool operator==(const modint&a,const modint&b){return a.x==b.x;}
friend constexpr bool operator!=(const modint&a,const modint&b){return a.x!=b.x;}
friend ostream&operator<<(ostream&os,const modint&a){return os<<a.x;}
friend istream&operator>>(istream&is,modint&a){long long v;is>>v;a=modint(v);return is;}
};
using mint = modint<998244353>;
namespace Combine{
const int Combine_max = 1e5 + 50;
mint fac[Combine_max];
void init() { fac[0] = 1; for (int i = 1; i < Combine_max; ++ i) fac[i] = fac[i - 1] * i; }
mint A(int n, int m) { return fac[n] / fac[n - m]; }
mint C(int n, int m) { return fac[n] / (fac[n - m] * fac[m]); }
mint fpow(mint x, int exp){
mint res = 1;
for (; exp; x *= x, exp >>= 1) if (exp & 1) res *= x;
return res;
}
}
signed main(){
mint a = 1000000000;
std::cout << a << "\n";
using namespace Combine;
init();
std::cout << C(5, 3) << "\n";
return 0;
}
DSU（不带持久化）
#include <bits/stdc++.h>
using namespace std;
struct DSU{
vector<int> parent;
void init(int k){
// 0 or 1-index ?
parent.resize(k + 1);
for (int i = 0; i <= k; ++ i) parent[i] = i;
}
int find(int x){
return parent[x] == x ? x : parent[x] = find(parent[x]);
}
void to_union(int x, int y){
parent[find(x)] = find(y);
}
bool is_same(int x, int y){
return find(x) == find(y);
}
};
// 按秩合并的 不一定需要
struct DSU{
vector<int> parent, rank;
void init(int K){
parent.resize(K), rank.resize(K);
for (int i = 0; i <= K; ++ i) parent[i] = i, rank[i] = 0;
}
int find(int x){
return (x == parent[x]) ? x : parent[x] = find(parent[x]);
}
void to_union(int to, int from){
int rto = find(to);
int rfrom = find(from);
if (rto == rfrom) return;
if (rank[rto] > rank[rfrom]) parent[rfrom] = rto;
else {
parent[rto] = rfrom;
if (rank[rto] == rank[rfrom]) ++ rank[rfrom];
}
}
bool is_same(int x, int y) {
return find(x) == find(y);
}
};
标签：std,常用,const,int,return,CodeForce,modint,模板,define 来源： https://www.cnblogs.com/Last--Whisper/p/15740209.html