摘要：http://acm.csu.edu.cn/OnlineJudge/problem.php?id=1030用线性筛素数果然快多了。#include<cstdio>#include<cstring>#include<cstdlib>#define MAXN 1300000bool is_p[MAXN];void calc(){ for( int i = 1; i < MAXN; i ++) is_p[i] = true; is_p[1] = false; for( int i = 2; i < MAXN; i ++) { if( !is_p[i.. 阅读全文

摘要：一维的广搜，从当前点到下个点有三种选择，然后求步数即可。用了STL的队列，然后忘了加using namespace std,检查浪费了时间。/*Accepted 860K 110MS C++ 640B 2012-05-26 20:44:59 */#include<cstdio>#include<cstring>#include<cstdlib>#include<queue>using namespace std;#define MAXN 100005int d[MAXN], N, K;void bfs(){ queue<int> q; 阅读全文

摘要：http://poj.org/problem?id=2488 好久没写回溯，题目要求骑士遍历全图，不能实现就输出“impossible”，首先遍历的方向要选好，字典序，其次判断遍历了全图的条件就是走了p*q-1步。初始点选取A1即可。/*Accepted 168K 16MS C++ 1267B 2012-07-23 15:35:53*/#include<cstdio>#include<cstring>#include<cstdlib>const int MAXN = 30;const int dx[] = {-2, -2, -1, -1, 1, 1, 2, 阅读全文

摘要：用hash写了一遍，hash的空间复杂度不是盖的/*Accepted 176460K 3907MS C++ 1006B 2012-05-25 09:13:41 */#include<cstdio>#include<cstring>#include<cstdlib>#define cal(x) ( (x + (1 << 29 | 1) * M) % MAX)#define LL __int64const int MAX = 20000001;const int M = 17531753;const int MAXN = 4005;int hash[ 阅读全文

摘要：今年暑假不AC，这是道很不错的贪心题，至于怎么贪呢，我们尽量选择结束时间靠前的节目，这样就可以保证在一定时间内能看到更多的题目。/*2012-05-07 12:29:59 Accepted 2037 0MS 268K 621 B C++ */#include<cstdio>#include<cstring>#include<cstdlib>const int MAXN = 105;typedef struct{ int s, e;}T;T Ti[MAXN];int cmp( const void *_p, const void *_q){ T *p = ( 阅读全文

摘要：枚举左边两个数的和以及右边两个数的和，用二分查找将其配对并计数。Hash的方法晚点再写。/*Accepted 49208K 5188MS C++ 1146B 2012-05-04 23:56:30 */#include<cstdio>#include<cstring>#include<cstdlib>#include<algorithm>using namespace std;#define MAXN 4005/*int cmp( const void *_p, const void *_q){ int *p = ( int *)_p; int 阅读全文

摘要：按照题目的要求我们将有generator的数标记，然后输出没标记的即可。/*Accepted 168K 16MS C++ 412B 2012-05-04 22:50:01 */#include<cstdio>#include<cstring>#include<cstdlib>bool is[10005];int main(){ int i, j, res, sum; memset( is, false, sizeof is); for( i = 1; i <= 10000; i ++) { if( !is[i]) { p... 阅读全文

摘要：先输入16个像素点，然后每输入一个像素点，输出与其最相近的像素点。/* Accepted 176K 0MS C++ 664B 2012-05-04 22:34:22 */#include<cstdio>#include<cstring>#include<cstdlib>#include<cmath>#define MAXN 20int A[MAXN], B[MAXN], C[MAXN];int a, b, c;int k;int main(){ for( int i = 0; i < 16; i ++) scanf( "%d%d% 阅读全文