oc--has such an integer 123456789, how to put the number of each digit of this integer, starting from the last place in the array, and traversing the reverse output string

There is an integer 123456789, how to put the number of each digit of this integer, starting from the last place in the array, and traversing
1Nsinteger num=123456789;2NSString *str=[[nsstring Alloc]initwithformat:@"%ld", num];3Nsmutablearray *arr=[Nsmutablearray array];4          for(Nsinteger i=str.length-1; i>=0; i--){5             //The string is truncated at the bottom, one at a time6NSString *str1=[str Substringwithrange:nsmakerange (i,1)];7 [arr addobject:str1];8         }9         //nsarray *sortarr=[arr sortedarrayusingselector: @selector (Class)];TenNSLog (@"first question-------------"); One          for(IDStrincharr) { ANSLog (@"%@", str); -}

1 //How to invert the string @ "abc123.xyz789"2NSString *STR1 =@"Uoy Evol I";3Nsmutablestring *str2=[[nsmutablestring alloc]initwithcapacity:str1.length];4Nsuinteger len=[str1 length];5          for(Nsinteger i= (len-1) ; I >=0; i--) {6[STR2 AppendFormat:@"%c", [str1 characteratindex:i]];//Notice that the char is returned here7}

Convert May 05, 2013 to 2013-05-05

Convert May 05, 2013 to 2013-05-05

1Nsmutablestring *str3=[[nsmutablestring Alloc]initwithformat:@"May 05, 2013"];2NSLog (@"The third question-------------");3NSLog (@"Original date:%@", STR3);4Nsrange RANGE1=[STR3 rangeofstring:@"years"];5         6[Str3 Replacecharactersinrange:nsmakerange (range1.location-1, range1.length+2) Withstring:@"-"];7Nsrange RANGE2=[STR3 rangeofstring:@"Month"];8[Str3 Replacecharactersinrange:nsmakerange (range2.location-1, range2.length+2) Withstring:@"-"];9Nsrange RANGE3=[STR3 rangeofstring:@"Day"];Ten[Str3 Replacecharactersinrange:nsmakerange (Range3.location, range3.length) withstring:@""]; OneNSLog (@"Date converted:%@", STR3);

oc--has such an integer 123456789, how to put the number of each digit of this integer, starting from the last place in the array, and traversing the reverse output string