Question

我的函数获取一组字符，大小，当前位置和计数器我需要在输入尺寸的长度上打印A，B，C （无AA和无CCC）的所有可能组合。
当大小超过3时，函数的值返回一个非合理的值，我没有找到它的原因。

int abc(char arr[],int lastPlace,int curPlace,int count){
    if (curPlace == lastPlace){
        arr[curPlace] = '\0';
        printf("%s, ", arr);
        return 1;    
    }
    if(!curPlace || arr[curPlace - 1] != 'A'){
        arr[curPlace] = 'A';
        count += abc(arr, lastPlace, curPlace + 1, 0);
    }
    arr[curPlace] = 'B';
    count += abc(arr, lastPlace, curPlace + 1, 0);
    if(curPlace < 2 || arr[curPlace - 1] != 'C' || arr[curPlace - 2] != 'C'){
        arr[curPlace] = 'C';
        count+=abc(arr, lastPlace, curPlace + 1, 0);
        if (curPlace == 0)
            return count;
    }
}

Answer 1

int abc(char arr[], int lastPlace, int curPlace, int count) 
{
    if (curPlace == lastPlace)
    {
        arr[curPlace] = '\0';
        printf("%s, ", arr);
        return 1;
    }
    if(!curPlace || arr[curPlace-1]!='A'){
        arr[curPlace] = 'A';
        count += abc(arr, lastPlace, curPlace + 1, 0);
    }

    arr[curPlace] = 'B';
    count += abc(arr, lastPlace, curPlace + 1, 0);

    if(curPlace < 2 || arr[curPlace - 1] != 'C' || arr[curPlace - 2] != 'C')
    {
        arr[curPlace] = 'C';
        count += abc(arr, lastPlace, curPlace + 1, 0);
    }
    return count;
}

为什么我从递归函数返回的值是错误的

1 个答案: