putchar

第一题：ACGT 题目链接： https://ac.nowcoder.com/acm/contest/931/A trie树、hash、map遍历 　　①、trie树上的节点多记一个rest值表示还有多少个串没被用。枚举所有串， 每次先在trie上跑匹配串，看一看那个点的rest。如果没法匹配的话就往trie里插入原串，把结束节点的rest+1 　　②、思路和trie类似。其实就是把trie换成hash。（把在树上跑换成去hash值） 　　③、将每个序列的个数存下，每次读入时判断对应序列的map的权值是否为0，若不为0，将输入序列和其对应序列的map权值-- ，ans++ 下面是第三种解法 ： 1 #include<bits/stdc++.h> 2 using namespace std; 3 #define ll long long 4 #define inf 0x3f3f3f 5 ll read() 6 { 7 ll res=0,flag=0; 8 char ch; 9 if((ch=getchar())=='-')flag=1; 10 else if(ch>='0'&&ch<='9')res=ch-'0'; 11 while((ch=getchar())>='0'&&ch<='9')res=res*10+(ch-'0'); 12 return flag?-res:res;

A.Math Problem（CF 1262 A） 题目大意：给定n条线段，求一条线段，使得这个线段能够跟所有给定的线段都相交（端点值一样也算相交），最小化它的长度，可以是0. 很显然找出这n条线段的左端点最大值和右端点的最小值，它们的差和0的最大值即为答案。 1 #include <bits/stdc++.h> 2 #define MIN(a,b) (((a)<(b)?(a):(b))) 3 #define MAX(a,b) (((a)>(b)?(a):(b))) 4 using namespace std; 5 6 template <typename T> 7 void read(T &x) { 8 int s = 0, c = getchar(); 9 x = 0; 10 while (isspace(c)) c = getchar(); 11 if (c == 45) s = 1, c = getchar(); 12 while (isdigit(c)) x = (x << 3) + (x << 1) + (c ^ 48), c = getchar(); 13 if (s) x = -x; 14 } 15 16 template <typename T> 17 void write(T x, char c = ' ') { 18 int b[40], l = 0; 19

I'm working through "The C Programming Language" by K&R and example 1.5 has stumped me: #include <stdio.h> /* copy input to output; 1st version */ int main(int argc, char *argv[]) { int c; while ((c = getchar()) != EOF) putchar(c); return 0; } I understand that 'getchar()' takes a character for 'putchar()' to display. However, when I run the program in terminal, why is it that I can pass an entire line of characters for 'putchar()' to display? Because your terminal is line-buffered. getchar() and putchar() still only work on single characters but the terminal waits with submitting the

I am running the following program from the C Programming Language book: #include <stdio.h> main() { int c; while((c=getchar()) != EOF) putchar(); } Or #include<stdio.h> int main(){ int c = getchar(); while(c != EOF){ putchar(c); c = getchar(); } } When I run this program, I get an unexplained behavior. If I input characters from the command line in the following sequence: {'h', 'e', 'l', 'l', 'o', '\n', '^D'} then I get the following response printed to screen: hello , after \n is input, and the program quits once ^D in entered. However, when I change the sequence as follows: {'h', 'e', 'l',

I'm reading The C Programming Language and have understood everything so far. However when I came across the getchar() and putchar() , I failed to understand what is their use, and more specifically, what the following code does. main() { int c; while ((c = getchar()) != EOF) putchar(c); } I understand the main() function, the declaration of the integer c and the while loop. Yet I'm confused about the condition inside of the while loop. What is the input in this C code, and what is the output. Sorry if this is a basic and stupid question, but I'm just looking for a simple explanation before I

【问题描述】 2兔八哥躲藏在树林旁边的果园里。果园有 M × N 棵树,组成一个 M 行 N 列的矩阵,水 平或垂直相邻的两棵树的距离为 1。兔八哥在一棵果树下。 猎人背着猎枪走进了果园,他爬上一棵果树,准备杀死兔八哥。 如果猎人与兔八哥之间没有其它的果树,猎人就可以看到兔八哥。 现己知猎人和兔八哥的位置,编写程序判断兔子所在的位置是否安全 【输入文件】 输入文件 rabbit.in 第一行为 n,表示有 n(n ≤ 100,000)组数据,每组数据的第一行为两 个正整数 ax 和 ay,表示猎人的位置,第二行为两个正整数 bx 和 by,表示兔八哥的位置(1 ≤ ax, ay, bx, by ≤ 100,000,000)。 【输出文件】 输出文件 rabbit.out 共有 n 行,每行为“yes”或“no”表示兔八哥的位置是否安全。 【输入 1】 1 1 1 1 2 【输出 1】 no 【输入 2】 1 1 1 1 3 【输出 2】 yes 没啥说的... 求直线上有无整数点 #include <iostream> #include <cstdio> #include <cmath> using namespace std; #define R register inline int gcd(int x,int y){return y?gcd(y,x%y):x;} int n;