string a, b; cin >> a >> b; ll cha = (a[0] — '0') * 600 + (a[1] — '0') * 60; ll mna = (a[3] — '0') * 10 + (a[4] — '0'); ll a1 = cha + mna; ll chb = (b[0] — '0') * 600 + (b[1] — '0') * 60; ll mnb = (b[3] — '0') * 10 + (b[4] — '0'); ll b1 = chb + mnb;