A. Cherry
贪心
#include <bits/stdc++.h>
#define all(a) a.begin(),a.end()
#define pb push_back
using namespace std;
using ll = long long ;
int test(int n){}
void solve()
{
int n;
cin>>n;
vector<ll>a(n+1);
for(int i=1;i<=n;i++)cin>>a[i];
long long int ans=0;
for(int i=2;i<=n;i++)
ans=max(ans,a[i]*a[i-1]);
cout<<ans<<"\n";
}
int main()
{
ios::sync_with_stdio(false);
int T=1;
cin>>T;
while(T--)
solve();
return 0;
}
B.Cobb
求i?j?k?(ai|aj) 的最大值
暴力加剪枝就行
#include <bits/stdc++.h>
#define all(a) a.begin(),a.end()
#define pb push_back
using namespace std;
using ll = long long ;
int test(){
int n,k;
cin>>n>>k;
vector<int>a(n+1);
for(int i=1;i<=n;i++)cin>>a[i];
int ans=-0x3f3f3f3f;
for(int i=1;i<=n;i++)
for(int j=i+1;j<=n;j++)
ans=max(ans,i*j-k*(a[i]|a[j]));
cout<<ans<<endl;
}
void solve()
{
int n,k;
cin>>n>>k;
vector<ll>a(n+1);
for(register int i=1,x;i<=n;i++) cin>>a[i];
ll res=-0x3f3f3f3f;
for(register ll i=n;i>=1;i--){
for(register ll j=i-1;j>=1;j--){
ll p=1ll*i*j-k*(a[i]|a[j]);
if(p>res) res=p;
if(i*j<res)break;
}
}
cout<<res<<"\n";
}
int main()
{
//freopen("out.txt","r",stdin);
ios::sync_with_stdio(false);
int T=1;
cin>>T;
while(T--)
solve();
return 0;
}
c.Mikasa
#include <iostream>
#include <cstring>
#define all(a) a.begin(),a.end()
#define pb push_back
using namespace std;
using ll = long long ;
void solve()
{
ll n,m;
scanf("%lld%lld",&n,&m);
ll ans=0x7fffffff;
for(ll i=32;i>=0;i--){
ll l=(n>>i)<<i,r=((m>>i)+1)<<i;
ans=min(ans,l^r);
}
printf("%d\n",ans);
}
int main()
{
int T=1;
scanf("%d",&T);
while(T--)
solve();
return 0;
}
D.Diane
如果是偶数...aabaaa...奇数末尾加个c
#include <iostream>
#include <cstring>
#define all(a) a.begin(),a.end()
#define pb push_back
using namespace std;
using ll = long long ;
void solve()
{
int n;
scanf("%d",&n);
if(n&1){
for(int i=1;i<n/2;i++)putchar(‘a‘);putchar(‘b‘);
for(int i=1;i<=n/2;i++)putchar(‘a‘);
if(n!=1)putchar(‘c‘);
}else{
for(int i=1;i<n/2;i++)putchar(‘a‘);putchar(‘b‘);
for(int i=1;i<=n/2;i++)putchar(‘a‘);
}puts("");
}
int main()
{
ios::sync_with_stdio(false);
int T=1;
scanf("%d",&T);
while(T--)
solve();
return 0;
}