Codeforces Round 920 (Div. 3)

A. Square

#include<bits/stdc++.h>
using namespace std;
void solve(){
	int a1,b1,a2,b2,a3,b3,a4,b4;
	cin>>a1>>b1>>a2>>b2>>a3>>b3>>a4>>b4;
	int s1,s2;
	if(a1==a2){
		s1=abs(b1-b2);
		s2=abs(b3-b4);
	}else if(a1==a3){
		s1=abs(b1-b3);
		s2=abs(b2-b4);
	}else if(a1==a4){
		s1=abs(b1-b4);
		s2=abs(b2-b3);
	}
	int ans=s1*s2;
	cout<<ans<<"\n";
}
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	int t=1;
	cin>>t;
	for(int i=1;i<=t;i++)solve();
	return 0;
} 

B. Arranging Cats

#include<bits/stdc++.h>
using namespace std;
void solve(){
	int n;
	string s1,s2;
	cin>>n>>s1>>s2;
	int cnt1=0,cnt2=0;
	for(int i=0;i<n;i++){
		if(s1[i]=='1'&&s2[i]=='0')cnt1++;
		if(s2[i]=='1'&&s1[i]=='0')cnt2++;
	}
	int ans=min(cnt1,cnt2)+(max(cnt1,cnt2)-min(cnt1,cnt2));
	cout<<ans<<"\n";
}
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	int t=1;
	cin>>t;
	for(int i=1;i<=t;i++)solve();
	return 0;
} 

C. Sending Messages

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e5+10;
int p[N];
void solve(){
	int n,k,a,b;
	cin>>n>>k>>a>>b;
	int f=0;
	for(int i=1;i<=n;i++)cin>>p[i];
	for(int i=1;i<=n;i++){
		int x=p[i]-p[i-1];
		if(x*a>b)k-=b;
		else k-=x*a;
		if(k<=0){
			f=1;
		}
	}
	if(k<=0)f=1;
	if(f){
		cout<<"NO\n";
	}else {
		cout<<"YES\n";
	}
}
signed main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	int t=1;
	cin>>t;
	for(int i=1;i<=t;i++)solve();
	return 0;
} 

D. Very Different Array 贪心+枚举位置

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e5+10;
int a[N],b[N];
void solve(){
	int n,m;
	cin>>n>>m;
	for(int i=1;i<=n;i++)cin>>a[i];
	for(int i=1;i<=m;i++)cin>>b[i];
	sort(a+1,a+1+n);
	sort(b+1,b+1+m,greater<int>());
	int ans=0;
    for(int i=1;i<=n;i++){
    	if(abs(a[i]-b[i])<abs(a[i]-b[m-n+i])){
    		ans+=abs(a[i]-b[m-n+i]);
		}else{
			ans+=abs(a[i]-b[i]);
		}
	}
	cout<<ans<<"\n"; 
}
signed main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	int t=1;
	cin>>t;
	for(int i=1;i<=t;i++)solve();
	return 0;
}