def appendAndDelete(s, t, k):
    prefix_count = 0
    len_s = len(s)
    len_t = len(t)
    while prefix_count < len(t):
        if prefix_count > (len_s - 1) or s[prefix_count] != t[prefix_count]:
            break
        else:
            prefix_count += 1
    
    delete_required = len_s - prefix_count
    addition_required = len_t - prefix_count
    total_ops_required = delete_required + addition_required
    if k >= (len_s + len_t):
        return "Yes"
        
    if k >= total_ops_required and (k - total_ops_required) % 2 == 0:
        return "Yes"
        
    return "No"