Question

我的功能是罗马数字到阿拉伯语转换功能的一部分。如果有一对CM，一对CD，其中有一个字符C，以及CM，CD，M，D和C的所有组合，它会评估很好。

但是，如果字符串中的最后一个字符是C（例如MCDCCC），则函数会在最终的“C”上崩溃。我已经在那里放了一堆NSLog来追踪问题，但我无法弄清楚为什么它会在最后的'C'上崩溃。

任何帮助欢迎，因为我一直试图弄清楚这一周。 PS，我把它重写为切换功能，但我遇到了同样的问题。

-(NSString *) decimalToRomanNumeral : (NSString*) romanNumeral
{
    NSLog(@"Roman Numeral       is %@", romanNumeral);

    int sumOfDecimals = 0;
    int stringLength = [romanNumeral length];
    NSLog(@"RomanNumeral Length is %i characters", stringLength);
    int arrayOfPrimitiveIntegers[stringLength];
    NSLog(@"Array Size          is %i spaces", stringLength);

    for (int c=0; c<[romanNumeral length]; c++)
    {
        NSLog(@"Character at       counter %i is %C", c, [romanNumeral characterAtIndex:c] );

        if ([romanNumeral characterAtIndex:c] == 'M')
        {
            NSLog(@"**********************************");
            NSLog(@"Within                 Evaluator M");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = 1000;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }
        else if (  ([romanNumeral length]>1 ) && (([romanNumeral characterAtIndex:c] == 'C') && ([romanNumeral characterAtIndex:c+1] == 'D'))  )
        {
            NSLog(@"**********************************");
            NSLog(@"Within                Evaluator CD");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = -100;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }
        else if (  ([romanNumeral length]>1 ) && (([romanNumeral characterAtIndex:c] == 'C') && ([romanNumeral characterAtIndex:c+1] == 'M'))  )
        {
            NSLog(@"**********************************");
            NSLog(@"Within                Evaluator CM");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = -100;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }
        else if ([romanNumeral characterAtIndex:c] == 'D')
        {
            NSLog(@"**********************************");
            NSLog(@"Within                 Evaluator D");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = 500;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }
        else if  (([romanNumeral length]==1 ) &&   ([romanNumeral characterAtIndex:c] == 'C'))
        {
            NSLog(@"**********************************");
            NSLog(@"Within                 Evaluator C");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = 100;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }        
        else if ([romanNumeral characterAtIndex:c] == 'C')
        {
            NSLog(@"**********************************");
            NSLog(@"Within               Evaluator C>1");
            NSLog(@"Counter                      is %i", c);
            arrayOfPrimitiveIntegers[c] = 100;
            NSLog(@"Value in Array at position %i is %i", c, arrayOfPrimitiveIntegers[c] );
            sumOfDecimals = sumOfDecimals + arrayOfPrimitiveIntegers[c];
            NSLog(@"Sum of Decimals              is %i", sumOfDecimals);
            NSLog(@"**********************************");
        }
    }
    NSString * numberString = [[NSString alloc]init];
    //numberString = [NSString stringWithFormat:@"%d", decimalNumber];
    return numberString;
}
@end

Answer 1

romanNumeral characterAtIndex:c+1 - 这似乎超出了最终循环迭代的范围。

您收到NSRangeException？

罗马数字到阿拉伯语

1 个答案: