poj 2739 Sum of Consecutive Prime Numbers (尺取法)

Fri, 25 Sep 2015 05:27:00 +0000

一开始迷之wa… 先找出素数下标的上界就可以A… 然后纠结了２０分钟．．．然后发现是预处理的素数少了一个素数．．我预处理是处理到＜１０００５的素数．．．最大数１００００,而超过１００００的第一个素数是１０００７这样判断终止条件就会死循环… sad

poj 2100 Graveyard Design (two pointers ，尺取法)

Thu, 24 Sep 2015 17:29:00 +0000

不多说，直接代码。

 1/*************************************************************************
 2	> File Name: code/poj/2100.cpp
 3	> Author: 111qqz
 4	> Email: rkz2013@126.com
 5	> Created Time: 2015年09月25日 星期五 00时42分49秒
 6 ************************************************************************/
 7
 8#include<iostream>
 9#include<iomanip>
10#include<cstdio>
11#include<algorithm>
12#include<cmath>
13#include<cstring>
14#include<string>
15#include<map>
16#include<set>
17#include<queue>
18#include<vector>
19#include<stack>
20#include<cctype>
21#define y1 hust111qqz
22#define yn hez111qqz
23#define j1 cute111qqz
24#define ms(a,x) memset(a,x,sizeof(a))
25#define lr dying111qqz
26using namespace std;
27#define For(i, n) for (int i=0;i<int(n);++i)
28typedef long long LL;
29typedef double DB;
30const int inf = 0x3f3f3f3f;
31LL n;
32LL maxn;
33vector<LL>ans;
34
35
36void solve()
37{
38 LL head = 1,tail = 1;
39 LL sum = 0 ;
40
41 while (tail<=maxn)
42 {
43	sum = sum + tail*tail;
44
45	if (sum>=n)
46	{
47	 while (sum>n)//主要是while，因为可能要减掉多个才能小于n
48	 {
49		sum -= head*head;
50		head++;
51	 }
52	 if (sum==n)
53	 {//因为要先输出答案个数...所以必须存起来延迟输出...
54		ans.push_back(head);
55		ans.push_back(tail);
56	 }
57	}
58	tail++;
59 }
60 LL sz = ans.size();
61 printf("%lld\n",sz/2);
62 for (LL i = 0 ; i<ans.size() ; i = i +2)
63 {
64	printf("%lld",ans[i+1]-ans[i]+1);
65	for ( LL j = ans[i] ; j <=ans[i+1] ; j++) printf(" %lld",j);
66	printf("\n");
67 }
68
69}
70int main()
71{
72 #ifndef ONLINE_JUDGE
73 freopen("in.txt","r",stdin);
74 #endif
75 scanf("%lld",&n);
76 maxn = ceil(sqrt(n));
77 solve();
78
79 #ifndef ONLINE_JUDGE
80 fclose(stdin);
81 #endif
82	return 0;
83}

尺取 on 111qqz's blog

poj 2739 Sum of Consecutive Prime Numbers (尺取法)

poj 2100 Graveyard Design (two pointers ，尺取法)