zoukankan      html  css  js  c++  java
  • Subsequence(二分)

    A sequence of N positive integers (10 < N < 100 000), each of them less than or equal 10000, and a positive integer S (S < 100 000 000) are given. Write a program to find the minimal length of the subsequence of consecutive elements of the sequence, the sum of which is greater than or equal to S.

    Input

    The first line is the number of test cases. For each test case the program has to read the numbers N and S, separated by an interval, from the first line. The numbers of the sequence are given in the second line of the test case, separated by intervals. The input will finish with the end of file.

    Output

    For each the case the program has to print the result on separate line of the output file.if no answer, print 0.

    Sample Input

    2
    10 15
    5 1 3 5 10 7 4 9 2 8
    5 11
    1 2 3 4 5

    Sample Output

    2
    3

    一开始c++交不过,g++过,原来是int 输入的时候是long long,wa了,g++交没这个问题

    代码:

    #include<cstdio>
    #include<iostream>
    #include<algorithm>
    #include<cstring>
    #include<map>
    #include<set>
    #include<stack>
    #include<queue>
    #include<cmath>
    
    const int maxn=1e5+5;
    typedef long long ll;
    using namespace std;
    ll a[maxn];
    ll s[maxn];
    ll n,ss;
    bool check(int x)
    {
        if(x>=n)
        {
        	return true;
    	}
    	for(int t=x;t<=n;t++)
    	{
    //		cout<<s[t]<<" "<<s[t-x+1]<<endl;
    		if(s[t]-s[t-x+1]>=ss)
    		{
    			
    			return true;
    		}
    	}
    	return false;
    }
    int  main()
    {
    	int  T;
    	cin>>T;
    	while(T--)
    	{
    		scanf("%lld%lld",&n,&ss);
    		for(int t=1;t<=n;t++)
    		{
    			scanf("%lld",&a[t]);
    		}
    		memset(s,0,sizeof(s));
    		for(int t=1;t<=n;t++)
    		{
    			s[t]=s[t-1]+a[t];
    		}
    		if(s[n]<ss)
    		{
    			cout<<"0"<<endl;
    	    }
    	    else
    	    {
    		int l=0,r=100000;
    		int mid;
    		while(l<=r)
    		{
    			mid=(l+r)/2;
    			if(check(mid))
    			{
    		      r=mid-1;
    			}
    			else
    			{
    			  l=mid+1;
    			}
    		}
    		mid=(l+r)/2;
    		cout<<mid<<endl;
    	   }
    	}
    	
    	return 0;
    }
  • 相关阅读:
    name mangling
    Haskell: What is Weak Head Normal Form
    取模运算和取余运算的区别
    a common method to rotate the image
    代码静态分析工具
    LeeCode-Single Number III
    七夕这天
    mysql TO_DAYS()
    (转)剖析Linux文件编码的查看及修改
    docker
  • 原文地址:https://www.cnblogs.com/Staceyacm/p/10781772.html
Copyright © 2011-2022 走看看