Codeforces

Educational Codeforces Round 132 (Rated for Div. 2)

B

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll N=1e5+5;
ll a[N],s1[N],s2[N],l,r,n,m;
int main(){
    scanf("%lld%lld",&n,&m);
    for(ll i=1;i<=n;i++) scanf("%lld",&a[i]);
    for(ll i=1;i<n;i++){
        if(a[i]<a[i+1]) s2[i]=a[i+1]-a[i];
        else s1[i]=a[i]-a[i+1];
    }
    for(ll i=1;i<n;i++){
        s1[i]=s1[i-1]+s1[i];
    }
    for(ll i=n-1;i;i--){
        s2[i]=s2[i+1]+s2[i];
    }
    for(ll i=1;i<=m;i++){
        scanf("%lld%lld",&l,&r);
        if(r>l) printf("%lld\n",s1[r-1]-s1[l-1]);
        else printf("%lld\n",s2[r]-s2[l]);
    }
    return 0;
}

CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!)

B

#include <bits/stdc++.h>
using namespace std;
int t,n,m,a;
int main(){
	scanf("%d",&t);
	while(t--){
		scanf("%d%d",&n,&m);
		int f=0,l=-1e9,r=1e9,ans=0;
		for(int i=1;i<=n;i++){
			scanf("%d",&a);
			l=max(l, a-m);
			r=min(r, a+m);
			if(l>r){
				l=a-m;
				r=a+m;
				ans++;
			}
		}
		printf("%d\n",ans); 
	}
	return 0;
}

Codeforces Round #813 (Div. 2)

B

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int N=1e5+5;
int t,n;
int main(){
	scanf("%d",&t);
	while(t--){
		scanf("%d",&n);
		if(n==1){
			printf("1");
		}
		else if(n==2){
			printf("2 1");
		}
		else if(n%2==0){
			for(int i=1;i<=n;i++){
				if(i%2==0) printf("%d ",i-1);
				else printf("%d ",i+1);
			}
		}
		else{
			printf("1 3 2 ");
			for(int i=4;i<=n;i++){
				if(i%2==0) printf("%d ",i+1);
				else printf("%d ",i-1);
			}
		}
		printf("\n");
	}
	return 0;
}

Codeforces Round #814 (Div. 2)

C

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int N=1e5+5;
const int INF=0x3f3f3f3f;
int t,n,q,a[N],s1[N],s2[N];
int main(){
	scanf("%d",&t);
	while(t--){
		memset(s1,0,sizeof(s1));
		memset(s2,0,sizeof(s2));
		scanf("%d%d",&n,&q);
		int m=0,id=0;
		for(int i=1;i<=n;i++){
			scanf("%d",&a[i]);
			if(a[i]>m){
				s1[a[i]]=i;
				s2[m]=i;
				m=a[i];
			}
		}
		for(int i=1;i<=q;i++){
			int x,y;
			scanf("%d%d",&x,&y);
			if(a[x]==m){
				if(s1[a[x]]>2)printf("%d\n",max(0,y-s1[a[x]]+2));
				else if(s1[a[x]]==1) printf("%d\n",max(0,y-s1[a[x]]+2)-1);
				else printf("%d\n",max(0,y-s1[a[x]]+2));
			}
			else{
				if(s1[a[x]]==0) printf("0\n");
				else {
					if(s1[a[x]]==1) printf("%d\n",max(0,min(y+2,s2[a[x]])-s1[a[x]]-1));
					else printf("%d\n",max(0,min(y+2,s2[a[x]])-s1[a[x]]));
				}
			}
		}
	}
	return 0;
}