S = input()
if '++' in S:
    x, y = map(int, S.split('++'))
    print(x - y)
    
elif '+-' in S:
    x, y = map(int, S.split('+-'))
    print(x + y)
    
elif '-+' in S:
    x, y = map(int, S.split('-+'))
    print(x + y)
    
elif '--' in S:
    x, y = map(int, input().split('--'))
    print(x - y)

else:
    if S[0] == '+':
        S = S[1:]
    if '+' in S:
        x, y = map(int, S.split('+'))
        print(x - y)
        
    else:
        if S[0] == '-':
            x = -1
            S = S[1:]
        else:
            x = 1
            
        X, y = map(int, S.split('-'))
        x *= X
        print(x + y)