▁very ▁next ▁year ▁( 2 6 1 ▁BC ), ▁ ▁Q in ▁general ▁Wang ▁He ▁( 王 <0xE9> <0xBD> <0x95> ) ▁attacked ▁Shang d ang , ▁and ▁the ▁Z ha o ▁general , ▁L ian ▁Po ▁( <0xE5> <0xBB> <0x89> <0xE9> <0xA0> <0x97> ), ▁led ▁ 2 0 0 , 0 0 0 ▁men ▁to ▁rein force ▁and ▁defend ▁the ▁region , ▁starting ▁the ▁biggest ▁and ▁blood iest ▁conflict ▁between ▁these ▁two ▁most ▁powerful ▁military ▁states . ▁ ▁After ▁his ▁v angu ard ▁forces ▁suffered ▁numerous ▁set back s , ▁L ian ▁Po ▁recognized ▁that ▁the ▁Z ha o ▁army ▁were ▁under power ed ▁against ▁their ▁Q in ▁enemies ▁in ▁field ▁batt les , ▁so ▁he ▁read just ed ▁the ▁strateg ies ▁and ▁d ug ▁in ▁with ▁a ▁ 1 0 0 ▁li - long ▁def ensive ▁line ▁near ▁Ch ang ping , ▁and ▁decided ▁to ▁wait ▁out ▁and ▁exhaust ▁the ▁Q in ▁supply ▁lines ▁( which ▁were ▁at ▁least ▁three ▁times ▁longer ▁than ▁Z ha o ' s , ▁hence ▁more ▁difficult ▁to ▁maintain ). ▁ ▁This ▁strategy ▁worked , ▁as ▁the ▁Q in ▁off ens ives ▁could ▁not ▁effectively ▁pen et rate ▁the ▁well - ent rench ed ▁Z ha o ▁positions ▁for ▁over ▁a ▁year . ▁ ▁Log ist ically ▁stra ined , ▁the ▁Q in ▁army ▁attempted ▁to ▁eng age ▁in ▁pitch ed ▁batt les , ▁but ▁L ian ▁Po ▁consist ently ▁refused ▁to ▁meet ▁them ▁in ▁open ▁batt les . ▁ ▁At ▁this ▁point , ▁both ▁sides ▁increased