指针神教几大高手码风分析
指针神教几大高手码风分析
时间线较乱, 比如 mycall 在年轻的时候使用的 id 为 wild_donkey.
根据高手闯出名声的时间顺序大概是 一扶苏一女士 然后 mycall 然后 3f 然后 young_tea, 但 一扶苏一女士 是 mycall 的学姐, mycall 是 3f 的引路人 (并非教练, 只是加入指针神教的引路人, 3f 和 young_tea 的教练都是 lxcool), 3f 是 young_tea 的亲哥.
由于不可抗力因素, 我们隐去了所有高手的性别信息, 不进行展示.
os / 编辑器 / 编译器
一扶苏一女士
windows 10.
vscode + mingw w64 (based on gcc-14).
mycall
windows 11.
vscode + mingw w64 (based on gcc-9).
3f
windows 11.
vscode + mingw w64 (based on gcc-15).
young_tea
macos, ubuntu 24.04.
xcode + gcc-14; vi + gcc-14.
语言标准
一扶苏一女士
c++ 20.
mycall
c++ 14.
3f
c++ 14 但更偏向 c 99.
young_tea
gnu++ 20.
缩进
一扶苏一女士
\(2\) 空格缩进.
mycall
\(2\) 空格缩进.
3f
\(2\) 空格缩进.
young_tea
tab 缩进, 长度 \(8\).
运算符
一扶苏一女士
运算符两边加空格.
mycall
运算符两边加空格.
3f
运算符两边无空格.
young_tea
运算符两边无空格.
内存管理
一扶苏一女士
new / 内存池, 并不 delete.
mycall
内存池.
3f
calloc 而不是 malloc, 严格 free.
young_tea
new, 严格 delete.
异常处理
算法竞赛严禁使用.
花括号
一扶苏一女士
左花括号在行尾, 右花括号单独占一行.
mycall
左花括号在行尾, 右花括号单独占一行.
3f
左花括号在行尾, 右花括号单独占一行.
young_tea
左花括号在行尾, 右花括号在行首, 右花括号后缩进然后直接写一行代码.
存图结构 (无权图和有权图大同小异)
一扶苏一女士
vector<int> e[maxn];
mycall
struct Edge;
struct Node {
Edge *Fst;
} N[200005];
struct Edge {
Edge *Nxt;
Node *To;
} E[400005], *cnte(E);
3f
typedef struct _edge {
int y; ll z; _edge *nxt;
} edge;
edge E[M]{}, *cnte(E), *e[N]{};
void addedge(int x, int y, ll z) {
(++cnte)->nxt = e[x]; e[x] = cnte;
cnte->y = y; cnte->z = z;
}
young_tea
class vtx{
public:
std::vector<vtx*>to;
void add_edge(vtx*);
} v[ver];
void vtx::add_edge(vtx *y){
to.emplace_back(y);
}
缺省源
一扶苏一女士
#include <bits/stdc++.h>
using ll = long long;
#ifdef ONLINE_JUDGE
#define freopen(a, b, c)
#endif
namespace IPT {
const int L = 1000000;
char buf[L], *front=buf, *end=buf;
char GetChar() {
if (front == end) {
end = buf + fread(front = buf, 1, L, stdin);
if (front == end) return -1;
}
return *(front++);
}
}
template <typename T>
inline void qr(T &x) {
char ch = IPT::GetChar(), lst = ' ';
while ((ch > '9') || (ch < '0')) lst = ch, ch=IPT::GetChar();
while ((ch >= '0') && (ch <= '9')) x = (x << 1) + (x << 3) + (ch ^ 48), ch = IPT::GetChar();
if (lst == '-') x = -x;
}
namespace OPT {
char buf[120];
}
template <typename T>
inline void qw(T x, const char aft, const bool pt) {
if (x < 0) {x = -x, putchar('-');}
int top=0;
do {OPT::buf[++top] = static_cast<char>(x % 10 + '0');} while (x /= 10);
while (top) putchar(OPT::buf[top--]);
if (pt) putchar(aft);
}
mycall
#include <bits/stdc++.h>
#define Wild_Donkey 0
#define foreplay for
#define wild while
using namespace std;
inline unsigned RD() {
unsigned intmp(0);
char rdch(getchar());
while (rdch < '0' || rdch > '9') rdch = getchar();
while (rdch >= '0' && rdch <= '9')
intmp = (intmp << 3) + (intmp << 1) + rdch - '0', rdch = getchar();
return intmp;
}
inline int RDsg() {
int rdtp(0), rdsg(1);
char rdch(getchar());
while ((rdch < '0' || rdch > '9') && (rdch != '-')) rdch = getchar();
if (rdch == '-') rdsg = -1, rdch = getchar();
while (rdch >= '0' && rdch <= '9')
rdtp = (rdtp << 3) + (rdtp << 1) + rdch - '0', rdch = getchar();
return rdtp * rdsg;
}
unsigned m, n;
unsigned A, B, C, D, t;
unsigned Cnt(0), Ans(0), Tmp(0);
signed main() {
// freopen(".in", "r", stdin);
// freopen(".out", "w", stdout);
// t = RD();
// for (unsigned T(1); T <= t; ++T){
// Clr();
return Wild_Donkey;
}
3f
#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
typedef long long ll;
typedef unsigned ui;
typedef unsigned long long ull;
typedef pair <int, int> pii;
typedef pair <int, ll> pil;
typedef pair <ll, int> pli;
typedef pair <ll, ll> pll;
#define pb emplace_back
#define pob pop_back
#define mp make_pair
#define ft first
#define sd second
#define bg begin
#define ed end
const ll
INF(0x3F3F3F3F3F3F3F3FLL),
Inf(0xC0C0C0C0C0C0C0C0LL),
Mod(998244353LL);
const int
N(1 << 18), M(1 << 19),
Q(1 << 18), LogN(18 + 1);
signed main() {
// freopen(".in", "r", stdin);
// freopen(".out", "w", stdout);
return strcmp("3Fnb!", "3Fnb!");
}
young_tea
#include<bits/stdc++.h>
using namespace std::string_literals;
using lf=double;
using ll=std::ptrdiff_t;
using ull=std::size_t;
using us=unsigned;
constexpr ll inf=0x3f3f3f3f3f3f3f3fl;
constexpr ll mod=0x3b800001l;
namespace yt{
template<class t>auto nxt(void)->t
{t x;std::cin>>x;return x;}
template<class t>void err(t x,bool _)
{std::cerr<<x;if(_)std::cerr<<" ak wf!\n"s;else std::cerr<<" "s;}
}
/*
prob link:
start think:
term think:
start code:
term code:
*/
auto main(void)->signed{
// std::freopen(".in","r",stdin);
// std::freopen(".out","w",stdout);
std::ios::sync_with_stdio(0);
std::cin.tie(nullptr);
std::cout.tie(nullptr);
ll _=1;
// _=yt::nxt<ll>();
while(_--)
solve();
return 0;
}
线段树
一扶苏一女士
struct Node {
Node *ls, *rs;
int l, r;
ll val, tag;
Node(int L, int R, const std::vector<ll> &a) : l(L), r(R), val(0), tag(0) {
if (L != R) {
int M = (L + R) >> 1;
ls = new Node(L, M, a);
rs = new Node(M + 1, R, a);
pushup();
} else {
ls = rs = nullptr;
val = a[L];
}
}
inline bool inRange(int L, int R) { return L <= l && r <= R; }
inline bool outRange(int L, int R) { return l > R || L > r; }
inline void pushup() { val = ls->val + rs->val; }
inline void pushdown() {
if (tag) {
ls->makeTag(tag);
rs->makeTag(tag);
tag = 0;
}
}
inline void makeTag(ll k) {
val += (r - l + 1) * k;
tag += k;
}
void upd(int L, int R, ll k) {
if (inRange(L, R)) {
makeTag(k);
} else if (!outRange(L, R)) {
pushdown();
ls->upd(L, R, k);
rs->upd(L, R, k);
pushup();
}
}
ll qry(int L, int R) {
if (inRange(L, R)) return val;
if (outRange(L, R)) return 0;
pushdown();
// std::cerr << l << ' ' << r << val << '\n';
return ls->qry(L, R) + rs->qry(L, R);
}
};
mycall
struct SgNode {
unsigned long long Val, Tag;
SgNode *L, *R;
} SgN[400005], *cntn(SgN);
void Udt(SgNode *x) {
x->Val = 0;
if (x->L) {
x->Val += x->L->Val;
}
if (x->R) {
x->Val += x->R->Val;
}
return;
}
void SgBld(SgNode *x, const int &l, const int &r) {
x->Tag = 0;
if (l == r) {
x->Val = a[l];
x->L = x->R = NULL;
return;
}
x->L = ++cntn;
x->R = ++cntn;
int mid((l + r) >> 1);
SgBld(x->L, l, mid);
SgBld(x->R, mid + 1, r);
Udt(x);
return;
}
inline bool Irg(const int &nl, const int &nr, const int &l, const int &r) {
return nl >= l && nr <= r;
}
inline bool Org(const int &nl, const int &nr, const int &l, const int &r) {
return nr < l || nl > r;
}
void PsDw(SgNode *x, const int &l, const int &r) {
if (x->Tag) {
if (l != r) {
int mid((l + r) >> 1);
x->L->Val += x->Tag * (mid - l + 1);
x->R->Val += x->Tag * (r - mid);
x->L->Tag += x->Tag;
x->R->Tag += x->Tag;
}
x->Tag = 0;
}
return;
}
void SgChg(SgNode *x, const int &l, const int &r, const int &yl, const int &yr,
const unsigned long long &yv) {
// printf("SgChg %d %d %d %d\n", x - SgN, l, r, x->Val);
if (Org(l, r, yl, yr)) {
return;
}
if (l == r) {
x->Val += yv;
return;
}
if (Irg(l, r, yl, yr)) {
x->Tag += yv;
x->Val += (r - l + 1) * yv;
x->Tag %= Mod;
x->Val %= Mod;
return;
}
int mid((l + r) >> 1);
if (!x) {
x = NULL;
}
PsDw(x, l, r);
if (!x->L) {
x->L = NULL;
}
SgChg(x->L, l, mid, yl, yr, yv);
if (!x->R) {
x->R = NULL;
}
SgChg(x->R, mid + 1, r, yl, yr, yv);
Udt(x);
return;
}
long long SgQry(SgNode *x, const int &l, const int &r, const int &yl,
const int &yr) {
if (Org(l, r, yl, yr)) {
return 0;
}
if (Irg(l, r, yl, yr)) {
return x->Val;
}
PsDw(x, l, r);
int mid((l + r) >> 1);
return (SgQry(x->L, l, mid, yl, yr) + SgQry(x->R, mid + 1, r, yl, yr)) % Mod;
}
3f
typedef struct _node{
int ls,rs;
ll val,tag;
}node;
int N,Q;
int rt,cntt;
node tr[NN<<2];
int x,y;
ll k;
void push_up(int p){
tr[p].val=tr[tr[p].ls].val+tr[tr[p].rs].val;
}
void push_down(int p,int l,int r){
if(tr[p].tag==0LL){
return;
}
int m=l+r>>1;
if(tr[p].ls==0){
tr[p].ls=++cntt;
}
if(tr[p].rs==0){
tr[p].rs=++cntt;
}
tr[tr[p].ls].val+=tr[p].tag*(m-l+1);
tr[tr[p].ls].tag+=tr[p].tag;
tr[tr[p].rs].val+=tr[p].tag*(r-m);
tr[tr[p].rs].tag+=tr[p].tag;
tr[p].tag=0LL;
}
void update(int *p,int l,int r){
if(*p==0){
*p=++cntt;
}
if(x<=l&&r<=y){
tr[*p].val+=k*(r-l+1);
tr[*p].tag+=k;
return;
}
int m=l+r>>1;
push_down(*p,l,r);
if(x<=m){
update(&tr[*p].ls,l,m);
}
if(m<y){
update(&tr[*p].rs,m+1,r);
}
push_up(*p);
}
void query(int p,int l,int r){
if(p==0){
return;
}
if(x<=l&&r<=y){
k+=tr[p].val;
return;
}
int m=l+r>>1;
push_down(p,l,r);
if(x<=m){
query(tr[p].ls,l,m);
}
if(m<y){
query(tr[p].rs,m+1,r);
}
}
young_tea
class tree{
tree *ld,*rd;
ll f,g,v,t;
public:
void push_up(void);
void push_down(void);
tree(ll,ll,ll*);
~tree(void);
void update(ll,ll,ll);
auto query(ll,ll,ll)->ll;
};
void tree::push_up(void){
v=ld->v+rd->v;
}
void tree::push_down(void){
if(t==0)
return;
ld->t+=t,rd->t+=t;
ld->v+=t*(ld->g-ld->f+1);
rd->v+=t*(rd->g-rd->f+1);
t=0;
}
tree::tree(ll p,ll q,ll *a){
f=p,g=q,v=t=0;
if(f==g){
v=a!=nullptr?a[f]:0;
return;
} ld=new tree(f,f+g>>1,a);
rd=new tree((f+g>>1)+1,g,a);
push_up();
}
tree::~tree(void){
if(ld!=nullptr)
delete ld,
ld=nullptr;
if(rd!=nullptr)
delete rd,
rd=nullptr;
}
void tree::update(ll p,ll q,ll k){
if(p<=f&&g<=q){
t+=k;
v+=k*(g-f+1);
return;
} push_down();
if(p<=ld->g)
ld->update(p,q,k);
if(rd->f<=q)
rd->update(p,q,k);
push_up();
}
auto tree::query(ll p,ll q,ll yy=0)->ll{
if(p<=f&&g<=q)
return v+yy*(g-f+1);
ll ct=0;
if(p<=ld->g)
ct+=ld->query(p,q,yy+t);
if(rd->f<=q)
ct+=rd->query(p,q,yy+t);
return ct;
}
指针哲学 (由 young_tea 总结, 不实之处请提出)
一扶苏一女士
管理数据结构, 但并不用于管理图.
mycall
离谱的指针.
3f
我哥的指针哲学就是个 dick, 用指针当成引用, 举例就是刚才那个该死的线段树.
young_tea
我用指针管理数据结构和图的顶点, 莫队也是适合使用指针维护区间, 因为莫队可以说是一种双指针.
原文来自CnBlogs, 作者: young_tea.
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