def solver(s):                           
    l = s                                
    while len(l) > 1:                    
        _l = []                          
        for i in range(len(l)-1):        
            tmp = int(l[i]) + int(l[i+1])
            if tmp >= 10:                
                tmp = 1 + (tmp - 10)     
            _l.append(str(tmp))          
        l = _l                           
    print(l[0])                          
T = int(input().strip())                 
for i in range(T):                       
    solver(input().strip())