Submission #161857

#	Time	Username	Problem	Language	Result	Execution time	Memory
161857		boolodifjenula	Lun (COCI19_lun)	Cpython 3	30 / 50	1085 ms	3428 KiB

lun

N=int(input())
S=input()
T=S[N-1]
z=0
if T=="x":
    for i in range(N-2,-1,-1):
        if N%2==0 and i%2==0 or N%2==1 and i%2==1:
            z+=(2*int(S[i]))%10+(2*int(S[i]))//10
        else:
            z+=int(S[i])
    print(z*9%10)
else:
    m=0
    T=int(T)
    x=0
    for i in range(N-2,-1,-1):
        if S[i]!="x" and (N%2==0 and i%2==0 or N%2==1 and i%2==1):
            z+=(2*int(S[i]))%10+(2*int(S[i]))//10
        elif S[i]!="x":
            z+=int(S[i])
        if S[i]=="x":
            m=i
    while 1:
        if N%2==0 and m%2==0 or N%2==1 and m%2==1:
            if (z+(2*x)%10+(2*x)//10)*9%10==T:
                print(x)
                break
        else:
            if (z+x)*9%10==T:
                print(x)
                break
                
            

• Subtask 1: 30 / 50