codeforces 732/D 二分

给出考试时间和考试需要准备的时间，问最早考完所有科目的时间 

二分答案 NlogN

二分抄神犇的写法 感觉挺舒服的嘻嘻嘻

#include<bits/stdc++.h>
using namespace std;
const int MAXN=1e5+5;
int N,M,d[MAXN],w[MAXN],cnt[MAXN];
void read(int &x){
    x=0;
    register char c=getchar();
    while(c<48||c>57)
        c=getchar();
    for(;c>=48&&c<=57;c=getchar())
        x=(x<<1)+(x<<3)+c-48;
}
bool check(int x)
{
    memset(cnt,0,sizeof(cnt));
    int ans = 0,val = 0;
    for (int i=x; i>=1; i--)
        if (d[i]&&++cnt[d[i]]==1&&w[d[i]]<i-M+ans+1)
        {
            ans++;
            val+=w[d[i]];
        }
   return ans == M && val+M<=x;
}
int main()
{
    read(N),read(M);
    for (int i=1; i<=N; i++)
        read(d[i]);
    for (int i=1; i<=M; i++)
        read(w[i]);
    int first = 0;
    int last = N;
    int mid;
    int best = -1;
    while (first <= last)
    {
        mid = (first + last)/2;
        if (check(mid))
        {
            last = mid-1;
            best = mid;
        }
        else
        {
            first = mid+1;
        }
    }
    printf("%d\n",best);
    return 0;
}