fread讀入掛and普通讀入掛and浮點數讀入掛
阿新 • • 發佈：2018-08-21
val sta digi lin scanf ... www. win 數據塊
fread讀入掛
版本一
namespace fastIO { #define BUF_SIZE 100000 //fread -> read bool IOerror = 0; 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<typename T> inline void read(T &x) { char ch; while(blank(ch = nc())); if(IOerror) return; for(x = ch - '0'; (ch = nc()) >= '0' && ch <= '9'; x = x * 10 + ch - '0'); } #undef BUF_SIZE }; using namespace fastIO;
版本二
struct FastIO { static const int S = 1e7; int wpos; char wbuf[S]; FastIO() : wpos(0) {} inline int xchar() { static char buf[S]; static int len = 0, pos = 0; if (pos == len) pos = 0, len = fread(buf, 1, S, stdin); if (pos == len) exit(0); return buf[pos++]; } inline int xuint() { int c = xchar(), x = 0; while (c <= 32) c = xchar(); for (; '0' <= c && c <= '9'; c = xchar()) x = x * 10 + c - '0'; return x; } inline int xint() { int s = 1, c = xchar(), x = 0; while (c <= 32) c = xchar(); if (c == '-') s = -1, c = xchar(); for (; '0' <= c && c <= '9'; c = xchar()) x = x * 10 + c - '0'; return x * s; } inline void xstring(char *s) { int c = xchar(); while (c <= 32) c = xchar(); for (; c > 32; c = xchar()) * s++ = c; *s = 0; } inline void wchar(int x) { if (wpos == S) fwrite(wbuf, 1, S, stdout), wpos = 0; wbuf[wpos++] = x; } inline void wint(LL x) { if (x < 0) wchar('-'), x = -x; char s[24]; int n = 0; while (x || !n) s[n++] = '0' + x % 10, x /= 10; while (n--) wchar(s[n]); wchar('\n'); } inline void wstring(const char *s) { while (*s) wchar(*s++); } ~FastIO() { if (wpos) fwrite(wbuf, 1, wpos, stdout), wpos = 0; } } io;
版本三
inline char nc(){ static char buf[100000],*p1=buf,*p2=buf; return p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++; } inline int _read(){ char ch=nc();int sum=0; while(!(ch>='0'&&ch<='9'))ch=nc(); while(ch>='0'&&ch<='9')sum=sum*10+ch-48,ch=nc(); return sum; }
版本四
#include<cstdio>
#include<iostream>
using namespace std;
const int maxx=40000008;
char Input[maxx+5],*ipos;
#define read() (strtol(ipos,&ipos,10))
int main() {
fread(Input,maxx,1,stdin);ipos=Input;
int n=read();
//Do something......
return 0;
}
版本五
const int STRSIZE=int(4e7);
char in1[STRSIZE];
char *in=in1, *tempend;
void Input() {
tempend=in+STRSIZE;
fread(in,1,STRSIZE,stdin);
}
inline void scan(int &x) {
char c=*(in++);
while(!(c>='0' && c<='9')) c=*(in++);
x=c-'0';
c=*(in++);
while(c>='0' && c<='9') {
x=x*10+c-'0';
c=*(in++);
}
}
版本六
const int BufferSize=1<<16;
char buffer[BufferSize],*head,*tail;
inline char Getchar() {
if(head==tail) {
int l=fread(buffer,1,BufferSize,stdin);
tail=(head=buffer)+l;
}
return *head++;
}
inline int read() {
int x=0,f=1;char c=Getchar();
for(;!isdigit(c);c=Getchar()) if(c=='-') f=-1;
for(;isdigit(c);c=Getchar()) x=x*10+c-'0';
return x*f;
}
inline void write(int x){
if(x>=10)write(x/10);
putchar(x%10+'0');
}
版本七
namespace IO {
const int MX = 4e7; //1e7占用內存11000kb
char buf[MX]; int c, sz;
void begin() {
c = 0;
sz = fread(buf, 1, MX, stdin);
}
inline bool read(int &t) {
while(c < sz && buf[c] != '-' && (buf[c] < '0' || buf[c] > '9')) c++;
if(c >= sz) return false;
bool flag = 0; if(buf[c] == '-') flag = 1, c++;
for(t = 0; c < sz && '0' <= buf[c] && buf[c] <= '9'; c++) t = t * 10 + buf[c] - '0';
if(flag) t = -t;
return true;
}
}
版本八
struct FastIO {
static const int S = 100 << 1;
int wpos;
char wbuf[S];
FastIO() : wpos(0) {}
inline int xchar() {
static char buf[S];
static int len = 0, pos = 0;
if (pos == len) {
pos = 0;
len = (int)fread(buf, 1, S, stdin);
}
if (pos == len) {
return -1;
}
return buf[pos++];
}
inline int xint() {
int s = 1, c = xchar(), x = 0;
while (c <= 32) {
c = xchar();
}
if (c == '-') {
s = -1;
c = xchar();
}
for (; '0' <= c && c <= '9'; c = xchar()) {
x = x * 10 + c - '0';
}
return x * s;
}
~FastIO() {
if (wpos) {
fwrite(wbuf, 1, wpos, stdout);
wpos = 0;
}
}
} io;
版本九：
namespace fastio{
int ptr, ye, Siz;
char temp[25], str[8333667], out[8333669];
void io_init(){
ptr = 0, ye = 0;
Siz = fread(str, 1, 8333667, stdin);
}
inline int read(){
int i, j, val = 0, fla = 1;
while (ptr<Siz&&(str[ptr] < 48 || str[ptr] > 57)) ptr++;
if(ptr>=Siz)return -1;
while (str[ptr] > 47 && str[ptr] < 58) fla = 0,val = (val * 10) + (str[ptr++] - 48);
if(fla)return -1;
return val;
}
inline void convert(long long x,bool flag){
int i, d = 0;
for (; ;){
temp[++d] = (x % 10) + 48;
x /= 10;
if (!x) break;
}
for (i = d; i; i--) out[ye++] = temp[i];
out[ye++] = ' ';
if(flag) out[ye-1] = 10;
}
inline void io_print(){
fwrite(out, 1, ye, stdout);
}
}
using namespace fastio;fread（）函數和fwrite（）函數：（可以用來實現對數據塊的操作）
// 讀取文件塊數據
size_t fread(void *buffer, size_t size, size_t count, FILE *file);
// 寫入文件塊數據
size_t fwrite(const void *buffer, size_t size, size_t count, FILE *file);fread參數說明：buffer是讀取數據後存放地址，size是的塊長度，count是塊的數量，實際讀取長度為sizecount，返回值為塊成功讀取塊的count數量。
fwrite參數說明：buffer是寫入數據後存放地址，size是的塊長度，count是塊的數量，實際讀取長度為sizecount，返回值為塊成功寫入快的count數量。
普通讀入掛
版本一：
int read(){
int sum=0;char ch=getchar();
while(!(ch>='0'&&ch<='9'))ch=getchar();
while(ch>='0'&&ch<='9')sum=sum*10+ch-48,ch=getchar();
return sum;
}strtok和sscanf結合輸入
/*
* 空格作為分隔輸入,讀取一行的整數
*/
gets(buf);
int v;
char *p = strtok(but, " ");
while (p){
sscanf(p, "%d", &v);
p = strtok(NULL," ");
}浮點數
inline bool scan_lf(double &num) {
char in;double Dec=0.1;
bool IsN=false,IsD=false;
in=getchar();
if(in==EOF) return false;
while(in!='-'&&in!='.'&&(in<'0'||in>'9'))
in=getchar();
if(in=='-'){IsN=true;num=0;}
else if(in=='.'){IsD=true;num=0;}
else num=in-'0';
if(!IsD){
while(in=getchar(),in>='0'&&in<='9'){
num*=10;num+=in-'0';}
}
if(in!='.'){
if(IsN) num=-num;
return true;
}else{
while(in=getchar(),in>='0'&&in<='9'){
num+=Dec*(in-'0');Dec*=0.1;
}
}
if(IsN) num=-num;
return true;
}
qsc的讀入掛：傳送門
fread讀入掛and普通讀入掛and浮點數讀入掛