the second question:
1 minute guy is the fastest, who will be the one run back and forth passing the flash light. This is the key
1 and 10 cross bridge - 10 min
1 return -              1 min
1 and 5 cross bridge -  5 min
1 return -              1 min
1 and 2 cross bridge -  2 min
------------------------------
                        19 min
let me give it a shot!
所有跟帖:
                    •                    
                    Liliac mm 好快啊!不过,题目要求用时 <19分钟。
                     -Learntoforget- 
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                        01/26/2010 postreply
                                                17:22:14
                    
                    
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                    奇怪,小于号没进去。“题目要求小于19分钟”
                     -Learntoforget- 
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                        01/26/2010 postreply
                                                17:24:52
                    
                    
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                    男人完了
                     -doitthen- 
                    ♂                    
                        
                    
                                                            
                        
                    
                                        
                    
                    
                                        
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                        01/26/2010 postreply
                                                17:36:46
                    
                    
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                    no, they have to cross the bridge with a flashlight.
                     -Learntoforget- 
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                        01/26/2010 postreply
                                                17:53:17
                    
                    
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                    ok try again!
                     -lilac09- 
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                        01/26/2010 postreply
                                                17:51:47
                    
                    
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                    Perfect! You got it! :)
                     -Learntoforget- 
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                        01/26/2010 postreply
                                                17:54:57
                    
                    
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                    男人完了
                     -doitthen- 
                    ♂                    
                        
                    
                                                            
                        
                    
                                        
                    
                    
                                        
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                        01/26/2010 postreply
                                                17:55:14
                    
                    
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                    美坛第一
                     -doitthen- 
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                        01/26/2010 postreply
                                                18:03:17
                    
                    
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                    那个大侠,您要让俺死的快,就直说~~
                     -lilac09- 
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                        01/26/2010 postreply
                                                18:13:39
                    
                    
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                    感觉很爽吧
                     -ryu,- 
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                        01/26/2010 postreply
                                                18:25:42
                    
                    
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                    嗯,跟您穿着小马甲蹦达的感觉还差一点点~~
                     -lilac09- 
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                        01/26/2010 postreply
                                                18:28:31
                    
                    
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                    you are bad
                     -doitthen- 
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                        01/26/2010 postreply
                                                18:28:50