NKOJ2322: OSU！

　　最简单的，贪心算法就可以解决。

#include<iostream>
using namespace std;
#define ll long long

int main()
{
    int n,v,result=0;
    cin>>n>>v;
    ll nt=-100;
    for(int i=0;i<n;++i)
    {
        ll tempT;
        cin>>tempT;
        if(tempT-nt>=v)
        {
            nt=tempT;
            ++result;
        }
    }
    cout<<result*100<<endl;
}

　　顺便放上最开始写的复杂不堪的dp

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
#define ll long long
struct line {
    ll left, right, val;
};

ll Max(int a, int b)
{
    return a > b ? a : b;
}

int findPreV(const vector<line>& lines, int L)//找到编号为L的线段前的线段编号
{
    int i;
    for (i = L-1; i >= 0; --i)
    {
        if (lines[i].right <= lines[L].left)
        {
            break;
        }
    }
    if (i == lines.size())
    {
        return -1;
    }
    return i ;
}

int v[100005];

int main()
{
    ios::sync_with_stdio(false);
    ll n,V;
    cin >> n>>V;
    if (V == 0)
    {
        cout << n * 100 << endl;
        return 0;
    }
    vector<line> lines(n);
    for (int i = 0; i < n; ++i)
    {
        int sec;
        cin >> sec;
        lines[i].left = sec;
        lines[i].right = sec+V;
        lines[i].val = 100;
    }
    v[0] = 0;
    v[1] = lines[0].val;
    for (int i = 2; i <= n; ++i)
    {
        int lineNum = i - 1;
        int preLineNum = findPreV(lines, lineNum);
        v[i] = Max(v[i - 1], v[preLineNum + 1] + lines[lineNum].val);
    }
    cout << v[n] << endl;
    //system("pause");
}