because you changed i, void desc(int i) <<== if i==0
{
if(i != str.length()-1) desc(++i); <<==i become 1
System.out.print(str.charAt(i)); <<== will print str.charAt(1);
};it will execute like thisdesc(0)
desc(1)
desc(2)
desc(3)
print "r"
i=3 now
print "r"
i=2 now
print "a"
i=1 now
printt "t"
{
if(i != str.length()-1) desc(++i); <<==i become 1
System.out.print(str.charAt(i)); <<== will print str.charAt(1);
};it will execute like thisdesc(0)
desc(1)
desc(2)
desc(3)
print "r"
i=3 now
print "r"
i=2 now
print "a"
i=1 now
printt "t"
解决方案 »
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