[1,2,3,4,5,6,7,8] 转换成 [(1,2),(2,3),(3,4),(4,5),(5,6),(6,7),(7,8)]

#[1,2,3,4,5,6,7,8]
#怎样倒腾成[(1,2),(2,3),(3,4),(4,5),(5,6),(6,7),(7,8)]

a=[1,2,3,4,5,6,7,8]
b=[]


for n,i in enumerate(a):


    print n,i


    if n<=6:
        #b[s]=
        b.append(tuple([a[n],a[n+1]])) #不能使用 s=0;b[s]=[a[n],a[n+1]] s+=1;会提示数组越界，因为b[s] 项不存在


    else:
        break;


print b