【DP】Codeforces Round #336 (Div. 2) C

我只是觉得人云亦云的写二分不好，这个题看了看数据范围，果然最快的方法还是暴力枚举吧。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
int n;
int f[1001000],next[1001000];
bool flag[1001000];
using namespace std;
int main()
{
	freopen("test.in","r",stdin);
    int x,y,tot=0;
    memset(f,0,sizeof(f));
    memset(next,0,sizeof(next));
    memset(flag,0,sizeof(flag));
    int ans=200000000,limitx=0;
    scanf("%d",&n);
    for (int i=1;i<=n;i++)
    {
        scanf("%d %d",&x,&y);
        next[x]=x-y;
        flag[x]=true;
    }
    for (int i=0;i<=1000100;i++)
    {
        if (flag[i]==false) 
        {
            if (i==0) f[i]=0;
            else f[i]=f[i-1];
            continue; 
        }
        tot++;
        if (next[i]-1<0) 
			f[i]=1;
        else
            f[i]=f[next[i]-1]+1;
        ans=min(ans,n-f[i]);
    }
    printf("%d",ans);
    return 0;
}