c - 找到矩阵行和列的最大总和，这是我得到的 2 个代码，其中 1 个有效，但另一个无效，尽管数组初始化是相同的

Question

在代码 1 中，数组运行时初始化工作正常，但在代码 2 中则不然，尽管这两个代码几乎相同

代码1:

#include<stdio.h>

int main()
{
    int n;
    scanf("%d",&n);
    int A[n][n],i,j;
    for(i=0;i<n;i++)
    {
        for(j=0;j<n;j++)
            scanf("%d",&A[i][j]);
    }
    int sum=0, newsum=0;
    for(i=0;i<n;i++)
    {
        newsum = 0;
        for(j=0;j<n;j++)
        {  
            newsum = newsum + A[i][j];
        }
        if(sum < newsum)
        {
            sum = newsum;
        }
    }
    return 0;
}

代码2:

#include<stdio.h>

int main()
{
    int dim,i,j,k,h=0;
    scanf("%d",k);
    int array[k][k];
    int max[2k+2]={0};

    for(i=0;i<k;i++)
    {
        for(j=0;j<k;j++)
        {
            scanf("%d",&array[i][j]);
        }
    }
    //rows
    h=max[0];
    for(i=0;i<k;i++)
    {
        for(j=0;j<k;j++)
        {
            max[i]+=array[i][j];

        }
        if(max[i]>=h)
        {
            h=max[i];
        }   
    }
    //columns 
    for(j=0;j<k;j++)
    {
        for(i=0;i<k;i++)
        {
            max[j+k]+=array[i][j];
        }
        if(max[j+k]>=h)
        {
            h=max[j+k];
        }

    }  
    //diagonal_1
    for(i,j=0;j<k && i<k;j++,i++) 
    {
        max[2k]+=array[i][j];
    }
    for(i=0,j=k-1;j>=0&&i<k;j--,i++) 
    { 
        max[2k+1]+=array[i][j];
    }          
    if(max[2k]>=max[2k+1])
        max[2k]=max[2k]; 
    else
        max[2k]=max[2k+1];

    if(max[2k]>=h)
        printf("%d",max[2k]);
    else
        printf("%d",h);   

    return 0;
}        

发生的错误是:

Program: In function 'main':
Program:11:9: error: fixed-point types not supported for this target
Program:48:6: warning: left-hand operand of comma expression has no effect[-       
Program:50:13: error: fixed-point types not supported for this target
Program:54:9: error: fixed-point types not supported for this  target    
Program:56:8: error: fixed-point types not supported for this target
Program:56:17: error: fixed-point types not supported for this target    
Program:57:5: error: fixed-point types not supported for this target 
Program:57:13: error: fixed-point types not supported for this target
Program:59:5: error: fixed-point types not supported for this target    
Program:59:13: error: fixed-point types not supported for this target 
Program:61:8: error: fixed-point types not supported for this target
Program:62:17: error: fixed-point types not supported for this target
Program:11:5: warning: unused variable 'max' [-Wunused-variable]

Answer 1

嗯，你不能使用像 int max[2k+2]={0} 这样的变量来声明数组，因为数组的大小必须在编译期间确定。