Problem: A word or a sentence in some language is called a pangram if all the characters of the alphabet of this language appear in it at least once. Pangrams are often used to demonstrate fonts in printing or test the output devices.

You are given a string consisting of lowercase and uppercase Latin letters. Check whether this string is a pangram. We say that the string contains a letter of the Latin alphabet if this letter occurs in the string in uppercase or lowercase.

Input

The first line contains a single integer n (1 ≤ n ≤ 100) — the number of characters in the string.

The second line contains the string. The string consists only of uppercase and lowercase Latin letters.

Output

Output "YES", if the string is a pangram and "NO" otherwise.

Examples

Input

12
toosmallword


Output

NO


Input

35
TheQuickBrownFoxJumpsOverTheLazyDog


Output

YES

Solution (in PYTHON3):

Solution:
#q1
'''
for _ in range(int(input())):
    l=list(map(int,input().split()))

    x=l[1]
    y=l[2]
    z=l[2]

    print(x,y,z)
'''  
#q2
'''
for _ in range(int(input())):

    x,n,m=map(int,input().split())
    
    while(x>20 and n>0 and x > x//2+10):
        x=x//2+10
        n-=1

    if(x <= m*10):
        print("YES ")
    else:
        print("NO ")
'''

#q3 
'''
def swap(s,j,mi):
    l=list(s)
    temp=l[j]
    l[j]=l[mi]
    l[mi]=temp

    s=''.join(l)

    return s

for _ in range(int(input())):

    s,t=input().split()

    k=0
    for i in range(len(s)):
        if ord(s[i]) < ord(t[i]):
            k=1
            break

        elif ord(s[i]) == ord(t[i]):
            continue

        else:
            mi=i
            for j in range(i+1,len(s)):
                if ord(s[j]) < ord(t[mi]):
                    s=swap(s,j,mi)
                    k=1
                    break
            break
    if k==1:
        print(s)

    else:
        print('---')

'''

#q4
'''
import math

def lcm(n):
    p=n
    t=int(math.sqrt(n))+1
    l=[0]*n
    l[0]=1
    
    while n%2 == 0:
        if n//2==2:
            l[2-1]+=1
        else:
            l[2-1]+=1
            l[(n//2)-1]+=1
        n=n//2

    for i in range(3,t):
        while n%i==0:

            if n//i==i:
                l[i-1]+=1
            else:
                l[i-1]+=1
                l[(n//i)-1]+=1
                
            n=n//i

    print(l)
    d=set()
    for i in range(p):
#        print('1')
        if l[i]!=0:
            d.add(pow((i+1),l[i]))
#            print('2')

    print(d)
    return list(d)
            
n=int(input())

f=lcm(n)
print(f)

if len(f)==1 or len(f)==2:
    print('1',n)

else:
    t1=f[1]
    t2=f[2]
    k=min(t1,t2)
    for i in range(3,len(f)):
        if t1==k:
            t1*=k
        else:
            t2*=k
        k=min(t1,t2)

    print(t1,t2)
        
'''     
        
#q5
'''
for _ in range(int(input())):

    string=input()
    i=0
    de=0
    z=[]
    
    while i<len(string)-2:

        if string[i:i+5]=="twone":
            de+=1
            z.append(i+2)
            i+=5

        elif string[i:i+3]=="one":
            de+=1
            z.append(i+1)
            i+=3

        elif string[i:i+3]=="two":
            de+=1
            z.append(i+1)
            i+=3       
            
        else:
            i+=1

    print(de)
    for i in range(len(z)):
        print(z[i]+1,end=" ")

    print()
'''        

#string modification ****
'''
for _ in range(int(input())):
    n=int(input())

    string=input()

    l=list(string)
    
    for k in range(n):
        first=n-k

        for i in range(first):
            second=i+k

            l[i:second+1:1]=l[second:i-1:-1]
            print(l)

    print(l)

'''

#remove adjacent
'''
n=int(input())

string=input()
l=list(string)
#print(l)
de=0

while(1):
    q=l
    a=[]
    t=0
    
    for i in range(1,len(l)):
        a.append(ord(q[i])-ord(q[i-1]))
    
    if((1 in a) or (-1 in a)) :
        for i in range(len(a)):
            if a[i]==-1:
                l.pop(i-t)
                t+=1
                de+=1
#                print(l)

            elif a[i]==1:
                l.pop(i+1-t)
                t+=1
                de+=1
#                print(l)

        print(l)
        
    else:
        break
print(de)
'''            


#Yet Another Counting Problem
'''
def gcd(a,b):
    if b==0:
        return a
    else:
        return gcd(b,a%b)

    
def solve(r,lcm,b):

    no_of_term=r//lcm
    product=no_of_term*lcm

    tot=r

    if product!=0:

        tot-=min(b,(r-product+1))
        tot-=(no_of_term-1)*b
        
    return tot-min(r,b-1)

for _ in range(int(input())):

    a,b,q=map(int,input().split())
    if a>b:
        a,b=b,a
        
    gc=gcd(a,b)
    product=a*b
    lcm=product//gc
    
    for i in range(q):
        l,r=map(int,input().split())

        ans1=solve(r,lcm,b)
        if l>=b:
            ans2=solve(l-1,lcm,b)
            ans=ans1-ans2
        else:
            ans=ans1
            
        print(ans,end=" ")
    print()
'''

#number game
'''
import math

import math

f='FastestFinger'
a='Ashishgup'
def prime(n):
    
    r=int(math.sqrt(n))+1
    
    if n%2==0 and n!=2:
        return False

    for i in range(3,r):
        if n % i ==0:
            return False
        
    return True
  
def solve(n):

    if n==0 :
        return
    elif n==1:
        return f
    
    dp=[]
    dp.append(0)
    
    
for _ in range(int(input())):

    n=int(input())
    if prime(n) and n>1:
        print("Ashishgup")
    else:
        print(solve(n))

'''

#Ciel and Flowers
'''
l=list(map(int,input().split()))
t=list(l)

su1=0

for i in range(3):
    su1+=int(l[i]/3)
    l[i]=l[i]%3
    
if min(l)!=0: 
    su1+=min(l)

q=min(t)
su2=q

for i in range(3):
    t[i]-=q

for i in range(3):
    su2+=int(t[i]/3)
    
print(max(su2,su1))
'''


#Count Subrectangles
'''
def row(n,m,k,c):

    l=[]
    for i in range(n):
        su=0
        for j in range(k):
            su+=c[i][j]
        l.append(su)

    for i in range():    

n,m,k=map(int,input().split())

a=list(map(int,input().split()))
b=list(map(int,input().split()))

c=[[0 for i in range(m)]for j in range(n)]

for i in range(n):
    for  j in range(m):
        c[i][j]=a[i]*b[j]

row(n,m,k,c)

'''  

#Ciel and Flowers
'''
a,b,c=map(int,input().split())

ans1=a//3+b//3+c//3
ans2=ans3=0

if a>0 and b>0 and c>0:
    a-=1
    b-=1
    c-=1

    ans2=a//3+b//3+c//3

    ans2+=1

if a>0 and b>0 and c>0 :
    a-=1
    b-=1
    c-=1

    ans3=a//3+b//3+c//3

    ans3+=2

print(max(ans1,ans2,ans3))
'''   

#Way Too Long Words
'''
for _ in range(int(input())):

    s=input()
    ans=""
    
    if len(s)>10:
        t=str(len(s)-2)
        ans+=s[0]+t+s[len(s)-1]

    else:
        ans+=s

    print(ans)
'''

#Progress Bar
'''
n,k,t=map(int,input().split())

a1=n*k

a2=t*a1/100

a3=int(a2/k)

s=int(a2-a3*k)

if s>0:
    for i in range(n):
        if i<a3:
            print(k,end=" ")
        elif i==a3:
            print(s,end=" ")
        else:
            print('0',end=" ")

else:
    for i in range(n):
        if i<a3:
            print(k,end=" ")

        else:
            print('0',end=" ")
    
'''

# Required Remainder
'''
for _ in range(int(input())):

    x,y,n=map(int,input().split())
    t1=n//x
    t2=t1*x
#    print(t1,t2)
    
    if y==0:
        print(t2)
    else:
        a=x-y
        
        if y+t2<=n:
            print(y+t2)
        else:
            print(t2-a)
'''   
    
'''
t1=12345//7
print(t1)
t2=t1*7
print(t2)
'''

# Multiply by 2, divide by 6
'''
import math

def factoriation(n):
    k=int(math.sqrt(n))+1
    
    l=[0]*k

    t=0
    l[0]=0
    l[1]=0
    
    
    while n%2==0:
        t+=1
        n=n//2
        
    l[2]=t

    for i in range(3,k):
        t=0
        while n%i==0:
            t+=1
            n=n//i
        l[i]=t
        
        if n==1:
            return l
        else:
            return [0,0,0,0]
        
    return l

for _ in range(int(input())):

    n=int(input())

    if n==6:
        print('1')

    elif n==3:
        print('2')

    elif n==1:
        print('0')
    
    elif n>=9:
        l=factoriation(n)

        if l[3] >= l[2] and l[3]!=0:
            ans=-1
            ans=l[2]
            l[3]=l[3]-l[2]
            l[2]=0

            ans+=l[3]*2

            print(ans)
            
        else:
            print('-1')

    else:
        print('-1')

'''

# Move Brackets
'''
for _ in range(int(input())):

    n=int(input())

    string=input()

    ans=0
    x2=0
    
    for i in range(n):
        if string[i]==')':
            if x2==0:
                ans+=1
            else:
                x2-=1

        elif string[i]=="(":
            x2+=1

    print(ans)
'''      

#Petya and Strings
'''
string1=input().lower()
string2=input().lower()

for i in range(len(string1)):

    if string1[i] > string2[i]:
        print('1')
        break
    elif string1[i] < string2[i] :
        print('-1')
        break
     
    else:
        if i==len(string1)-1:
            print('0')
            break
        else:
            continue
'''

#Helpful maths
'''
string=input()
li=list(string.split("+"))
l=[0]*3

li.sort()

for i in range(len(li)):
    if i!=len(li)-1:
        print(li[i]+'+',end="")
    else:
        print(li[i])
'''

#word capitalisation
'''
string=input()

if ord(string[0])>96:
    print(chr(ord(string[0])-32)+string[1:])

else:
    print(string)
'''

#Boy or Girl
'''
string=input()

l=[0]*26

for i in range(len(string)):
    l[ord(string[i])-97]+=1

k=0
for i in range(26):
    if l[i]>0:
        k+=1

if k%2==0:
    print('CHAT WITH HER!')
else:
    print('IGNORE HIM!')
'''

#Translation
'''
s=input()
t=input()

k=""

for i in range(len(s)-1,-1,-1):
    k+=s[i]

if k==t:
    print("YES")
else:
    print("NO")

'''

#Word
'''
string=input()
lower=0
upper=0


for i in range(len(string)):
    if ord(string[i])>96:
        lower+=1

    else:
        upper+=1

if upper>lower:
    print(string.upper())

else:
    print(string.lower())
            
'''

# Anton and Danik
'''
n=int(input())

string=input()

A=0
D=0

for i in range(n):
    if string[i]=="A":
        A+=1
    else:
        D+=1

if A>D:
    print('Anton')
elif A<D:
    print("Danik")

else:
    print("Friendship")
'''

#Football
'''
string=input()
a=b=0

for i in range(len(string)):

    if string[i]=='0':
        a+=1
        b=0

    else:
        b+=1
        a=0

    if a==7 or b==7:
        t=1
        break

    else:
        t=0

if t==1:
    print("YES")
else:
    print("NO")
'''

#Dubstep
'''
string=input()
s=""
i=0
while i<len(string)-2:

    if string[i]=="W" and string[i+1]=="U" and string[i+2]=="B":
        i+=3
        s+=" "

    else:
        s+=string[i]
        i+=1

if i>=len(string):    
    print(' '.join(s.split()))
    
else:
    s+=string[i]
    i+=1
    
    if i>=len(string):
        print(' '.join(s.split()))
    else:
        s+=string[i]
        print(' '.join(s.split()))
'''

#Two_gram
'''
n=int(input())
string=input()

res=0

for i in range(len(string)-1):
    cur=0
    for j in range(i,len(string)-1):

        if string[i]==string[j] and string[i+1]==string[j+1]:
            cur+=1

    if res < cur:

        res=cur
        ans=string[i]+string[i+1]

print(ans)
'''

#Even But Not Even
'''
for _ in range(int(input())):

    n=int(input())
    string=input()
    l=list(string)
    su=0
    
    for i in range(len(string)-1,-1,-1):
        su+=int(l[i])
        if l[i]=="0":
            l.pop(i)
#    print(su)
    if su%2!=0:
        if int(string)%2==0:
            for i in range(len(l)-1,-1,-1):
                if int(l[i])%2==0:
                    l.pop(i)
                else:
                    break
            for i in range(len(l)-2,-1,-1):
                if int(l[i])%2!=0:
                    l.pop(i)
                    break
                
            if len(l)>1:   
                print(''.join(i for i in l))

            else:
                print('-1')
                
        else:
#            print(l)
            for i in range(len(l)-2,-1,-1):
                if int(l[i])%2!=0:
                    l.pop(i)
                    break

            if len(l)>2:
                print(''.join(i for i in l))
            elif len(l)==2 and int(l[0])%2!=0:
                print(''.join(i for i in l))
            else:
                print('-1')

    else:
#        print(su)
        if int(string)%2!=0:
            print(''.join(i for i in l))
        else:
            for i in range(len(l)-1,-1,-1):
                if int(l[i])%2==0:
                    l.pop(i)
                else:
                    break
            if len(l)>1:
                print(''.join(i for i in l))
            else:
                print('-1')

'''

# Delete from the Left
'''
s=input()
t=input()
q=0


i1=len(t)-1
i2=len(s)-1
    
while i1>=0 and i2>=0:
    if s[i2]==t[i1]:
        q+=1
        i1-=1
        i2-=1
            
    else:
        break


su1=len(s)-q
#print(su1,q)
su2=len(t)-q
print(su1+su2)

'''

#Important exam
'''
n,m=map(int,input().split())
k=[]
    
for i in range(n):
    string=input()
    l=list(string)
    k.append(l)

q=list(map(int,input().split()))
su=0

for i in range(m):
    t1=t2=t3=t4=t5=0

    for j in range(n):
        if k[j][i]=="A":
            t1+=1

        elif k[j][i]=="B":
            t2+=1

        elif k[j][i]=="C":
            t3+=1

        elif k[j][i]=="D":
            t4+=1

        else:
            t5+=1

    a=max(t1,t2,t3,t4,t5)
    su+=a*q[i]

print(su)
            
'''

# Letters Rearranging
'''
for _ in range(int(input())):

    string=input()
    t=1
    j=0
    
    for i in range(len(string)-1):
        if string[i] == string[i+1]:
            t+=1
        else:
            j=i+1
            break

    if t==len(string):
        print('-1')
        
    else:
        k=0
        for i in range(len(string)//2):
            if string[i]==string[len(string)-1-i]:
                k+=2

        if len(string)%2==0 and k==len(string):
            l=list(string)
            l[0],l[j]=l[j],l[0]
            print(''.join(i for i in l))

        elif len(string)%2==1 and k==len(string)-1:
            l=list(string)
            l[0],l[j]=l[j],l[0]
            print(''.join(i for i in l))

        else:
            print(string)
'''

#Romaji
'''
string=input()
t=0

if string[len(string)-1]=='n' or string[len(string)-1]=='a' or string[len(string)-1]=='e' or string[len(string)-1]=='i' or string[len(string)-1]=='o' or string[len(string)-1]=='u':
    t=1
    for i in range(0,len(string)-1):

        if (string[i]!='n' or string[i]!='a' or string[i]!='e' or string[i]!='i' or string[i]!='o' or string[i]!='u') and (string[i+1]=='a' or string[i+1]=='e' or string[i+1]=='i' or string[i+1]=='o' or string[i+1]=='u'):
            t=1
            
        elif (string[i]=='a' or string[i]=='e' or string[i]=='i' or string[i]=='o' or string[i]=='u') and string[i+1]=='a' or string[i+1]=='e' or string[i+1]=='i' or string[i+1]=='o' or string[i+1]=='u':
            t=1
            
        elif string[i]=='n':
            t=1

        elif string[i]=='a' or string[i]=='e' or string[i]=='i' or string[i]=='o' or string[i]=='u':
            t=1
            
        else:
            t=0
            break

else:
    t=0
        
if t==0:
    print('NO')
else:
    print("YES")

'''

#String Task
'''
string=input().lower()

l=['a','e','i','o','u','y']
k=list(string)
i=0

while i <len(k):
    if k[i] in l:
        k.pop(i)
    else:
        i+=1
        
for i in range(len(k)):
    
    print('.'+k[i],end="")
'''

#chat room
'''
string=input().lower()

if len(string)<5:
    print("NO")
else:
    l=['h','e','l','l','o']
    k=list(string)
    i=0
    
    while i<len(k):
        if k[i]==l[0]:
            l.pop(0)
            i+=1

        else:
            i+=1

        if len(l)==0:
            break

    if len(l)==0:
        print("YES")
    else:
        print("NO")

'''

#cAPS lOCK
'''
string=input()

a1=a=b=0
l=list(string)

if ord(l[0])<91:
    a1+=1
else:
    a1=0
    
for i in range(1,len(string)):

    if ord(l[i])<91:
        b+=1

if a1==0 and b==len(l)-1:
    for i in range(len(l)):
        if i==0:
            print(chr(ord(l[i])-32),end="")
        else:
            print(chr(ord(l[i])+32),end="")
        
elif a1==1 and b==len(l)-1:
    for i in range(len(l)):
        print(chr(ord(l[i])+32),end="")

else:
    print(string)
    
'''

#Lecture
'''
n,m=map(int,input().split())
q1=[]
q2=[]

for i in range(m):
    a,b=input().split()
    q1.append(a)
    q2.append(b)

k=input()

l=list(k.split())

for i in range(n):

    a=q1.index(l[i])
    if len(q1[a]) > len(q2[a]):
        print(q2[a],end=" ")
    else:
        print(q1[a],end=" ")
'''

# Football
'''
l=[1,0]

t=int(input())
string=input()

for i in range(1,t):

    n=input()
    if n==string:
        l[0]+=1
    else:
        j=n
        l[1]+=1

if l[0]>l[1]:
    print(string)

else:
    print(j)
'''

#Pangram

n=int(input())

string=input().lower()
l=[0]*26

if n>=26:
    
    for i in range(n):
        l[ord(string[i])-97]+=1

    if min(l)!=0:
        print("YES")
    else:
        print("NO")

else:
    print("NO")