比賽連結：https://codeforces.com/contest/2033
A. Sakurako and Kosuke
直接模擬好吧
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<deque>
#include<cctype>
#include<string.h>
#include<math.h>
#include<time.h>
#include<random>
#include<stack>
#include<string>
#define lowbit(x) (x & -x)
using namespace std;
mt19937 rnd(time(0));
typedef long long ll;
const ll mod=1e9+7;
const ll N=2e5+5;
ll ksm(ll x,ll y)
{
ll ans=1;
while(y)
{
if(y&1)
ans=(ans%mod*x%mod)%mod;
x=x%mod*(x%mod)%mod;
y>>=1;
}
return ans%mod%mod;
}
ll gcd(ll x,ll y)
{
if(y==0)
return x;
else
return gcd(y,x%y);
}
void fio()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int main()
{
fio();
ll t;
cin>>t;
while(t--)
{
ll n;
cin>>n;
ll cnt=-1;
ll ans=1;
ll i=1;
ll gs=1;
while(cnt<=n&&cnt>=-n)
{
gs++;
if(i%2==1)
{
cnt+=(2*gs-1);
}
else
{
cnt-=(2*gs-1);
}
i++;
ans++;
}
if(ans%2==0)
{
cout<<"Kosuke"<<endl;
}
else
{
cout<<"Sakurako"<<endl;
}
}
}
B. Sakurako and Water
直接統計主對角線最大負數然後取正加起來就好
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<deque>
#include<cctype>
#include<string.h>
#include<math.h>
#include<time.h>
#include<random>
#include<stack>
#include<string>
#define lowbit(x) (x & -x)
using namespace std;
mt19937 rnd(time(0));
typedef long long ll;
const ll mod=1e9+7;
const ll N=2e5+5;
ll ksm(ll x,ll y)
{
ll ans=1;
while(y)
{
if(y&1)
ans=(ans%mod*x%mod)%mod;
x=x%mod*(x%mod)%mod;
y>>=1;
}
return ans%mod%mod;
}
ll gcd(ll x,ll y)
{
if(y==0)
return x;
else
return gcd(y,x%y);
}
void fio()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
ll a[600][600];
int main()
{
fio();
ll t;
cin>>t;
while(t--)
{
ll n;
cin>>n;
map<ll,ll>q;
for(ll i=1;i<=n;i++)
{
for(ll j=1;j<=n;j++)
{
cin>>a[i][j];
if(a[i][j]<0)
{
q[i-j]=min(q[i-j],a[i][j]);
}
}
}
ll ans=0;
for(ll i=1;i<=n;i++)
{
for(ll j=1;j<=n;j++)
{
if(q[i-j]<0)
{
ans+=abs(q[i-j]);
q[i-j]=0;
}
}
}
cout<<ans<<endl;
}
}
C. Sakurako's Field Trip
從中心進行擴散，然後考慮影響即可
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<deque>
#include<cctype>
#include<string.h>
#include<math.h>
#include<time.h>
#include<random>
#include<stack>
#include<string>
#define lowbit(x) (x & -x)
using namespace std;
mt19937 rnd(time(0));
typedef long long ll;
const ll mod=1e9+7;
const ll N=2e5+5;
ll ksm(ll x,ll y)
{
ll ans=1;
while(y)
{
if(y&1)
ans=(ans%mod*x%mod)%mod;
x=x%mod*(x%mod)%mod;
y>>=1;
}
return ans%mod%mod;
}
ll gcd(ll x,ll y)
{
if(y==0)
return x;
else
return gcd(y,x%y);
}
void fio()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
ll a[250000];
int main()
{
fio();
ll t;
cin>>t;
while(t--)
{
ll n;
cin>>n;
for(ll i=1;i<=n;i++)cin>>a[i];
ll l=(n+1)/2;
ll r=(n+2)/2;
while(l>=1)
{
ll k=l;
ll u=r;
l--;
r++;
if(l==0)
break;
if(a[l]==a[k]&&a[r]==a[u]&&a[l]!=a[r])
{
swap(a[l],a[r]);
}
else if(a[l]==a[k]&&a[r]!=a[u])
{
swap(a[l],a[r]);
}
else if(a[r]==a[u]&&a[l]!=a[k])
{
swap(a[l],a[r]);
}
}
ll ans=0;
for(ll i=1;i<=n-1;i++)
{
if(a[i]==a[i+1])ans++;
}
cout<<ans<<endl;
}
}
D. Kousuke's Assignment
從左邊起，如果每次能湊一對就直接拿，然後清空map
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<deque>
#include<cctype>
#include<string.h>
#include<math.h>
#include<time.h>
#include<random>
#include<stack>
#include<string>
#define lowbit(x) (x & -x)
using namespace std;
mt19937 rnd(time(0));
typedef long long ll;
const ll mod=1e9+7;
const ll N=2e5+5;
ll ksm(ll x,ll y)
{
ll ans=1;
while(y)
{
if(y&1)
ans=(ans%mod*x%mod)%mod;
x=x%mod*(x%mod)%mod;
y>>=1;
}
return ans%mod%mod;
}
ll gcd(ll x,ll y)
{
if(y==0)
return x;
else
return gcd(y,x%y);
}
void fio()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
ll a[250000];
int main()
{
fio();
ll t;
cin>>t;
map<ll,ll>q;
while(t--)
{
q.clear();
ll n;
cin>>n;
ll ans=0;
q[0]++;
ll l=0;
for(ll i=1;i<=n;i++)
{
cin>>a[i];
a[i]+=a[i-1];
if(q[a[i]-a[l]]>0)
{
q.clear();
q[0]++;
ans++;
l=i;
continue;
}
q[a[i]-a[l]]++;
}
cout<<ans<<endl;
}
}
E. Sakurako, Kosuke, and the Permutation
仔細想想只要不符合的湊一下就好了，這種湊得是第二種，然後模擬一遍即可
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<deque>
#include<cctype>
#include<string.h>
#include<math.h>
#include<time.h>
#include<random>
#include<stack>
#include<string>
#define lowbit(x) (x & -x)
using namespace std;
mt19937 rnd(time(0));
typedef long long ll;
const ll mod=1e9+7;
const ll N=2e5+5;
ll ksm(ll x,ll y)
{
ll ans=1;
while(y)
{
if(y&1)
ans=(ans%mod*x%mod)%mod;
x=x%mod*(x%mod)%mod;
y>>=1;
}
return ans%mod%mod;
}
ll gcd(ll x,ll y)
{
if(y==0)
return x;
else
return gcd(y,x%y);
}
void fio()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
ll a[2500000];
bool vis[2500000];
ll b[2500000];
int main()
{
fio();
ll t;
cin>>t;
while(t--)
{
ll n;
cin>>n;
for(ll i=1;i<=n;i++)
{
cin>>a[i],vis[i]=0;
b[a[i]]=i;
}
ll ans=0;
for(ll i=1;i<=n;i++)
{
if(vis[i])continue;
if(a[a[i]]==i)
{
vis[i]=1;
vis[a[i]]=1;
}
else if(a[i]==i)
{
vis[i]=1;
}
else
{
// 3 1
ll u=a[a[i]],j=a[b[i]];
swap(a[a[i]],a[b[i]]);//
//cout<<a[a[i]]<<" "<<a[b[i]]<<endl;
swap(b[u],b[j]);
vis[i]=1;
vis[a[i]]=1;
ans++;
}
}
cout<<ans<<endl;
}
}