Codeforce466A——贪心——DZY Loves Sequences

http://codeforces.com/problemset/problem/446/A

/*
贪心,开前缀后缀,枚举,每个i
*/
/************************************************
* Author        :Powatr
* Created Time  :2015-8-16 20:03:03
* File Name     :cf466A.cpp
 ************************************************/

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <sstream>
#include <cstring>
#include <cmath>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <list>
#include <map>
#include <set>
#include <bitset>
#include <cstdlib>
#include <ctime>
using namespace std;

#define lson l, mid, rt << 1
#define rson mid + 1, r, rt << 1 | 1
typedef long long ll;
const int MAXN = 1e5 + 10;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
int a[MAXN];
int pre1[MAXN], pre2[MAXN];
int main(){
    int n;
    while(~scanf("%d", &n)){
        for(int i = 1; i <= n; i++)
            scanf("%d", &a[i]);
        for(int i = 1; i <= n; i++)
            pre1[i] = pre2[i] = 1;
        for(int i = 2; i <= n; i++){
            if(a[i] > a[i-1])
                pre1[i] = pre1[i-1] + 1;
        }
        for(int i = n - 1; i >= 1; i--){
            if(a[i+1] > a[i]){
                pre2[i] = pre2[i+1] + 1;
            }
        }
        int ans = 1;
        if(n > 1) ans = max(pre1[n-1] + 1, pre2[2] + 1);
            for(int i = 2; i <= n - 1; i++){
                if(a[i+1] - a[i-1] >= 2){
                    ans = max(ans, pre1[i-1] + pre2[i+1] + 1);
                }
                else {
                    ans = max(ans , pre1[i-1] + 1);
                    ans = max(ans, pre2[i+1] + 1);
                }
        }
        printf("%d
", ans);
    }
    return 0;
}

  

原文地址:https://www.cnblogs.com/zero-begin/p/4734915.html