July Cook-Off 2017

分析:因为按位或最后肯定小于等于加，所以把所有数按位或即可

 1 #include "iostream"
 2 #include "cstdio"
 3 #include "cstring"
 4 using namespace std;
 5 const int maxn=1e5+10;
 6 long long a[maxn];
 7 int T,n;
 8 int main()
 9 {
10     cin>>T;
11     while(T--)
12     {
13         scanf("%d",&n);
14         long long res=0;
15         for(int i=1;i<=n;i++){
16             cin>>a[i];
17             res|=a[i];
18         }
19         cout<<res<<endl;
20     }
21     return 0;
22 }

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Chang and the Perfect Function

分析：我们求出每一个sqrt(i*i+y)-i,最后加起来即可

 1 #include "iostream"
 2 #include "cstdio"
 3 #include "cstring"
 4 #include "string"
 5 #include "cmath"
 6 using namespace std;
 7 long long a,b;
 8 int main()
 9 {
10     cin>>a>>b;
11     long long d=0;
12     for(long long i=1;i<=a;i++){
13         long long res=i*i+b;
14         long long c=sqrt(res);
15         d+=c-i;
16     }
17     cout<<d<<endl;
18 }

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