在面試中稳强，經(jīng)常被問到字符串倒序的面試題，下面提供兩種簡單的實(shí)現(xiàn)：
第一種：
- (NSString*)reverseWordsInString:(NSString*)oldStr{
NSMutableString *newStr = [[NSMutableString alloc] initWithCapacity:oldStr.length];
for (int i = (int)oldStr.length - 1; i >= 0; i --) {
? ? unichar character = [oldStr characterAtIndex:i];
? ? [newStr appendFormat:@"%c",character];
}
return newStr;
}
第二種：
- (NSString*)reverseWordsInString:(NSString*)oldStr
{
NSMutableString *newStr = [NSMutableString stringWithCapacity:oldStr.length];
[str enumerateSubstringsInRange:NSMakeRange(0, oldStr.length) options:NSStringEnumerationReverse | NSStringEnumerationByComposedCharacterSequences? usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop){
[newStr appendString:substring];
}];
return newStr;
}
