快速读入输出挂

1 fread 和 fwrite 实现的超级读入输出挂(速度超快，但不支持终端交互）

2 getchar 和 putchar 实现的读入输出挂（比1慢一些，但支持终端交互）

3 整合1和2两个版本，通过本地宏定义，实现本地运行版本2，提交时运行1.（保留了两个版本的优势，又避免了两个版本的缺陷）

#include<bits/stdc++.h> namespace fastIO { #define BUF_SIZE 100000//缓存区大小 #define DECIMAL 6 //double 类型的 默认输出保留位数 #define LL long long bool IOerror = 0;//是否读到文件末尾 inline char nc() { static char buf[BUF_SIZE], * p1 = buf + BUF_SIZE, * pend = buf + BUF_SIZE; if (p1 == pend) { p1 = buf; pend = buf + fread(buf, 1, BUF_SIZE, stdin); if (pend == p1) { IOerror = 1; return -1; } }return *p1++; } inline bool blank(char ch) { return ch == ' ' || ch == '\n' || ch == '\r' || ch == '\t'; } template<class T> inline bool read(T& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (sign)x = -x; return true; } inline bool read(unsigned long long& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(unsigned int& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(double& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (ch == '.') { double tmp = 1; ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())tmp /= 10.0, x += tmp * (ch - '0'); }if (sign)x = -x; return true; } inline bool read(char* s) { char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())*s++ = ch; *s = 0; return true; } inline bool read(char& c) { for (c = nc(); blank(c); c = nc()); if (IOerror) { c = -1; return false; }return true; } inline bool read(std::string& s) { s.clear(); char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())s += ch; return true; } template<class T, class... U>bool read(T& h, U&... t) { return read(h) && read(t...); } struct Ostream_fwrite { char* buf, * p1, * pend; Ostream_fwrite() { buf = new char[BUF_SIZE]; p1 = buf; pend = buf + BUF_SIZE; } inline void out(char ch) { if (p1 == pend) { fwrite(buf, 1, BUF_SIZE, stdout); p1 = buf; }*p1++ = ch; } template<class T>inline void print(T x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; if (x < 0)out('-'), x = -x; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(char ch) { out(ch); } inline void print(unsigned long long x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(unsigned int x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(double x, int y = DECIMAL) { static LL mul[] = { 1,10,100,1000,10000,100000,1000000,10000000,100000000, 1000000000,10000000000LL,100000000000LL,1000000000000LL,10000000000000LL, 100000000000000LL,1000000000000000LL,10000000000000000LL,100000000000000000LL }; if (x < -1e-12)out('-'), x = -x; x *= mul[y]; LL x1 = (LL)floor(x); if (x - floor(x) >= 0.5)++x1; LL x2 = x1 / mul[y], x3 = x1 - x2 * mul[y]; print(x2); if (y > 0) { out('.'); for (size_t i = 1; i < y && x3 * mul[i] < mul[y]; out('0'), ++i); print(x3); } } inline void print(char* s) { while (*s)out(*s++); } inline void print(const char* s) { while (*s)out(*s++); } inline void print(std::string s) { print(s.c_str()); } inline void flush() { if (p1 != buf) { fwrite(buf, 1, p1 - buf, stdout); p1 = buf; } } ~Ostream_fwrite() { flush(); } }Ostream; template<class T>inline void print(T x) { Ostream.print(x); } template<class T>inline void println(T x) { Ostream.print(x); Ostream.out('\n'); } inline void print(double x, int y = DECIMAL) { Ostream.print(x, y); } inline void println(double x, int y = DECIMAL) { Ostream.print(x, y); Ostream.out('\n');; } template<class T, class... U>void print(const T& h, const U&... t) { print(h); Ostream.out(' ');; print(t...); } template<class T, class... U>void println(const T& h, const U&... t) { print(h); Ostream.out(' ');; println(t...); } inline void flush() { Ostream.flush(); } // C int,long long ,__int128,unsigned long long,unsigned int,double,char[],char // c++ string #undef LL #undef DECIMAL #undef BUF_SIZE }; using namespace fastIO; int main() { #ifdef DEBUG freopen("..\\DEBUG\\IO\\1.in", "r", stdin); #endif // 使用二进制文件读写 fread 和 fwrite 实现的超级输入输出挂 //因为是文件读写，不能在终端进行输入，需要重定向从文件读入 。但输出可以在终端显示 //如果有在终端交互的需求，把 fread 换成 getchar，fwrite 换成putchar 即可 //getchar的读取速度 介于 fread 和 scanf 之间 ， putchar 同理 //支持 int,long long ,__int128,unsigned long long,unsigned int,double,char[],char，string 类型的 输入输出 //其中 double类型 输出时的默认精度 1e-12,默认保留位数是小数点后六位 ，也可以指定保留位数 int a; long long b; unsigned long long c; unsigned int d; double e; char f[10]; char g; std::string h; // 1 2 3 4 3.14 hello y world read(a, b, c, d, e, f, g, h);//使用了可变参数列表 支持多类型丶多参数混合 print(a, b, c, d, e, f, g, h);//各参数之间以一个空格相隔，末尾不含空格 println(a, b, c, d, e, f, g, h);//各参数之间以一个空格相隔，末尾追加换行符 println("hello", 3.14, 3); println(3.1415926);//默认四舍五入 保留六位小数 println(3.1415926, 4);//指定保留 4 位 println(3.1415926, 9);//指定保留 9 位 //需要注意的是 在多个参数时，无法指定保留位数，只能以默认六位输出 println(3.1415926, 4, "hello");// 输出 3.141592 4 "hello" 此时 4 作为int 类型 输出 //所以如果需要指定保留位数，需要单独调用 //while(scanf("%d",&x)!=EOF) // 等价于 while(read(x)) // read 返回 布尔类型 false 代表读到文件 末尾 fastIO::flush();//释放缓存区 return 0; }

支持终端交互的版本

#include<bits/stdc++.h> namespace fastIO { #define DECIMAL 6 //double 类型的 默认输出保留位数 #define LL long long bool IOerror = 0;//是否读到文件末尾 inline char nc() { char ch = getchar(); if (ch == -1)IOerror = 1; return ch; } inline bool blank(char ch) { return ch == ' ' || ch == '\n' || ch == '\r' || ch == '\t'; } template<class T> inline bool read(T& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (sign)x = -x; return true; } inline bool read(unsigned long long& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(unsigned int& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(double& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (ch == '.') { double tmp = 1; ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())tmp /= 10.0, x += tmp * (ch - '0'); }if (sign)x = -x; return true; } inline bool read(char* s) { char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())*s++ = ch; *s = 0; return true; } inline bool read(char& c) { for (c = nc(); blank(c); c = nc()); if (IOerror) { c = -1; return false; }return true; } inline bool read(std::string& s) { s.clear(); char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())s += ch; return true; } template<class T, class... U>bool read(T& h, U&... t) { return read(h) && read(t...); } struct OStream { inline void out(char ch) { putchar(ch); } template<class T>inline void print(T x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; if (x < 0)out('-'), x = -x; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(char ch) { out(ch); } inline void print(unsigned long long x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(unsigned int x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(double x, int y = DECIMAL) { static LL mul[] = { 1,10,100,1000,10000,100000,1000000,10000000,100000000, 1000000000,10000000000LL,100000000000LL,1000000000000LL,10000000000000LL, 100000000000000LL,1000000000000000LL,10000000000000000LL,100000000000000000LL }; if (x < -1e-12)out('-'), x = -x; x *= mul[y]; LL x1 = (LL)floor(x); if (x - floor(x) >= 0.5)++x1; LL x2 = x1 / mul[y], x3 = x1 - x2 * mul[y]; print(x2); if (y > 0) { out('.'); for (size_t i = 1; i < y && x3 * mul[i] < mul[y]; out('0'), ++i); print(x3); } } inline void print(char* s) { while (*s)out(*s++); } inline void print(const char* s) { while (*s)out(*s++); } inline void print(std::string s) { print(s.c_str()); } }Ostream; template<class T>inline void print(T x) { Ostream.print(x); } template<class T>inline void println(T x) { Ostream.print(x); Ostream.out('\n'); } inline void print(double x, int y = DECIMAL) { Ostream.print(x, y); } inline void println(double x, int y = DECIMAL) { Ostream.print(x, y); Ostream.out('\n');; } template<class T, class... U>void print(const T& h, const U&... t) { print(h); Ostream.out(' ');; print(t...); } template<class T, class... U>void println(const T& h, const U&... t) { print(h); Ostream.out(' ');; println(t...); } // C int,long long ,__int128,unsigned long long,unsigned int,double,char[],char // c++ string #undef LL #undef DECIMAL #undef BUF_SIZE }; using namespace fastIO; int main() { //稍作修改 将 fread 和fwrite 换成了 getchar putchar 以支持终端交互 输入输出 //同时也不需要数组来充当缓存区了 int a; long long b; unsigned long long c; unsigned int d; double e; char f[10]; char g; std::string h; // 1 2 3 4 3.14 hello y world read(a, b, c, d, e, f, g, h);//使用了可变参数列表 支持多类型丶多参数混合 print(a, b, c, d, e, f, g, h);//各参数之间以一个空格相隔，末尾不含空格 println(a, b, c, d, e, f, g, h);//各参数之间以一个空格相隔，末尾追加换行符 println("hello", 3.14, 3); println(3.1415926);//默认四舍五入 保留六位小数 println(3.1415926, 4);//指定保留 4 位 println(3.1415926, 9);//指定保留 9 位 //需要注意的是 在多个参数时，无法指定保留位数，只能以默认六位输出 println(3.1415926, 4, "hello");// 输出 3.141592 4 "hello" 此时 4 作为int 类型 输出 //所以如果需要指定保留位数，需要单独调用 //while(scanf("%d",&x)!=EOF) // 等价于 while(read(x)) // read 返回 布尔类型 false 代表读到文件 末尾 return 0; }

整合后的版本3

（我将宏LOCAL 定义在了 头文件 stdc++.h 里面，这样引用stdc++就有LOCAL的定义）

#include<bits/stdc++.h> namespace fastIO { #ifdef LOCAL #define DEBUG #endif #define BUF_SIZE 100000 #define DECIMAL 6 #define LL long long static bool IOerror = 0; #ifdef DEBUG inline char nc() {char ch = getchar();if (ch == -1)IOerror = 1;return ch;} #else inline char nc() { static char buf[BUF_SIZE], * p1 = buf + BUF_SIZE, * pend = buf + BUF_SIZE; if (p1 == pend) { p1 = buf; pend = buf + fread(buf, 1, BUF_SIZE, stdin); if (pend == p1) { IOerror = 1; return -1; } }return *p1++; } #endif inline bool blank(char ch) { return ch == ' ' || ch == '\n' || ch == '\r' || ch == '\t'; } template<class T> inline bool read(T& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (sign)x = -x; return true; } inline bool read(unsigned long long& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(unsigned int& x) { char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; return true; } inline bool read(double& x) { bool sign = 0; char ch = nc(); x = 0; for (; blank(ch); ch = nc()); if (IOerror)return false; if (ch == '-')sign = 1, ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())x = x * 10 + ch - '0'; if (ch == '.') { double tmp = 1; ch = nc(); for (; ch >= '0' && ch <= '9'; ch = nc())tmp /= 10.0, x += tmp * (ch - '0'); }if (sign)x = -x; return true; } inline bool read(char* s) { char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())*s++ = ch; *s = 0; return true; } inline bool read(char& c) { for (c = nc(); blank(c); c = nc()); if (IOerror) { c = -1; return false; }return true; } inline bool read(std::string& s) { s.clear(); char ch = nc(); for (; blank(ch); ch = nc()); if (IOerror)return false; for (; !blank(ch) && !IOerror; ch = nc())s += ch; return true; } template<class T, class... U>bool read(T& h, U&... t) { return read(h) && read(t...); } struct Ostream_fwrite { #ifdef DEBUG inline void out(char ch) { putchar(ch); } #else char* buf, * p1, * pend; Ostream_fwrite() { buf = new char[BUF_SIZE]; p1 = buf; pend = buf + BUF_SIZE; } inline void out(char ch) { if (p1 == pend) { fwrite(buf, 1, BUF_SIZE, stdout); p1 = buf; }*p1++ = ch; } #endif template<class T>inline void print(T x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; if (x < 0)out('-'), x = -x; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(char ch) { out(ch); } inline void print(unsigned long long x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(unsigned int x) { static char s[41], * s1; s1 = s; if (!x)*s1++ = '0'; while (x)*s1++ = x % 10 + '0', x /= 10; while (s1-- != s)out(*s1); } inline void print(double x, int y = DECIMAL) { static LL mul[] = { 1,10,100,1000,10000,100000,1000000,10000000,100000000, 1000000000,10000000000LL,100000000000LL,1000000000000LL,10000000000000LL, 100000000000000LL,1000000000000000LL,10000000000000000LL,100000000000000000LL }; if (x < -1e-12)out('-'), x = -x; x *= mul[y]; LL x1 = (LL)floor(x); if (x - floor(x) >= 0.5)++x1; LL x2 = x1 / mul[y], x3 = x1 - x2 * mul[y]; print(x2); if (y > 0) { out('.'); for (size_t i = 1; i < y && x3 * mul[i] < mul[y]; out('0'), ++i); print(x3); } } inline void print(char* s) { while (*s)out(*s++); } inline void print(const char* s) { while (*s)out(*s++); } inline void print(std::string s) { print(s.c_str()); } #ifndef DEBUG inline void flush() { if (p1 != buf) { fwrite(buf, 1, p1 - buf, stdout); p1 = buf; } } ~Ostream_fwrite() { flush(); } #endif // !DEBUG }Ostream; template<class T>inline void print(T x) { Ostream.print(x); } template<class T>inline void println(T x) { Ostream.print(x); Ostream.out('\n'); } inline void print(double x, int y = DECIMAL) { Ostream.print(x, y); } inline void println(double x, int y = DECIMAL) { Ostream.print(x, y); Ostream.out('\n');; } template<class T, class... U>void print(const T& h, const U&... t) { print(h); Ostream.out(' ');; print(t...); } template<class T, class... U>void println(const T& h, const U&... t) { print(h); Ostream.out(' ');; println(t...); } #ifndef DEBUG inline void flush() { Ostream.flush(); } #endif #undef LL #undef DECIMAL #undef BUF_SIZE //本地 getchar/putchar ，提交 fread/fwrite //本地支持终端交互输入输出 }; using namespace fastIO; typedef long long LL; using namespace std; const int32_t MAXN = 1e5 + 5; int main() { #ifdef LOCAL freopen("..\\DEBUG\\IO\\1.in", "r", stdin); // freopen("my.out", "w", stdout); clock_t c1 = clock(); #endif #ifdef LOCAL std::cerr << "Time:" << clock() - c1 << "ms" << std::endl; #endif #ifndef DEBUG fastIO::flush(); #endif return 0; }