Question

至少应具有4个功能：input，output，compute 和main
没有全局变量
printf或scanf函数中没有compute和main

我的代码当前给我错误：

#include <stdio.h>

void input(int* arr[50][50],int* r,int* c);
int compute(int* r,int* c,int result);

int ouput(int* arr[50][50],int* r,int* c,int result);


int main(void)
{
    int arr_in[50][50];

    int result = 0;
    int r_in = 0;
    int* r = &r_in;

    int c_in = 0;
    int* c = &c_in;

    input(arr_in,&r_in,&c_in);
    compute(&r_in,&c_in,result);
    output(arr_in,&r_in,&c_in,result);

}

void input(int* arr[50][50],int* r,int* c)
{
    printf("Enter the no. of rows: ");
    scanf("%d",c);

    printf("Enter the no. of columns: ");
    scanf("%d",r);

    printf("Enter the elements of the matrix\n");
    for(int i = 0;i < *r;i ++)
    {
        for(int j = 0;j < *c;j++)
        {
            printf("Enter element[%d][%d]: ",i + 1,j + 1);
            scanf("%d",arr[i][j]);
        }
    }
}

int compute(int* r,int* c,int result)
{
    if(*r == *c)
    {
        result = 1;
        return result;
    }
    else
    {
        result = 0;
        return result;
    }

}

int output(int* arr[50][50],int* r,int* c,int result)
{
    if(result == 1)
    {
        for(int i = 0;i < *r;i++)
        {
                for(int j = 0;j < *c;j++)
                {
                    if(i==j)
                        printf("%d\t",*arr[j][i]);    
                    else
                        printf("\t");   
                }
                printf("\n");         
            }
    }

    else
    {
         printf("\nMatrix is not a Square Matrix.");
    }
    return 0;
}

错误：

>diagonal.c:20:11: error: incompatible pointer types passing 'int [50][50]' to parameter of type 'int *(*)[50]'
      [-Werror,-Wincompatible-pointer-types]
    input(arr_in,&r_in,&c_in);
          ^~~~~~

diagonal.c:3:17: note: passing argument to parameter 'arr' here
void input(int* arr[50][50],int* r,int* c);
                ^
diagonal.c:22:11: error: incompatible pointer types passing 'int [50][50]' to parameter of type 'int *(*)[50]'
      [-Werror,-Wincompatible-pointer-types]
    ouput(arr_in,&r_in,&c_in,result);
          ^~~~~~
diagonal.c:6:16: note: passing argument to parameter 'arr' here
int ouput(int* arr[50][50],int* r,int* c,int result);
               ^
2 errors generated.

Answer 1

您刚刚传递了错误的参数。如果将2D数组作为int arr[50][50]传递，则编译器会将其作为指向指针的指针处理，您无需在数据类型之后添加（*）。因此原型必须如下：

void input(int arr[50][50],int* r,int* c);
int ouput(int arr[50][50],int* r,int* c,int result);

第二点是compute函数。您更改compute函数的局部变量而不是传递的变量。因此您应该按如下方式更改原型：

int compute(int* r,int* c,int *result);

并按如下所示调用函数：

compute(&r_in,&c_in,&result);

最后，整个代码如下：

#include <stdio.h>

void input(int arr[50][50],int* r,int* c);
void compute(int* r,int* c,int *result);

int ouput(int arr[50][50],int* r,int* c,int result);


int main(void)
{
    int arr_in[50][50];

    int result = 0;
    int r_in = 0;
    int* r = &r_in;

    int c_in = 0;
    int* c = &c_in;

    input(arr_in,&r_in,&c_in);
    compute(&r_in,&c_in,&result);
    output(arr_in,&r_in,&c_in,result);

}

void input(int arr[50][50],int* r,int* c)
{
    int i, j;
    printf("Enter the no. of rows: ");
    scanf("%d",c);

    printf("Enter the no. of columns: ");
    scanf("%d",r);

    printf("Enter the elements of the matrix\n");
    for(i = 0;i < *r;i ++)
    {
        for(j = 0;j < *c;j++)
        {
            printf("Enter element[%d][%d]: ",i + 1,j + 1);
            scanf("%d",&arr[i][j]);
        }
    }
}

void compute(int* r,int* c,int *result)
{
    if(*r == *c)
    {
        *result = 1;
    }
    else
    {
        *result = 0;
    }

}

int output(int arr[50][50],int* r,int* c,int result)
{
    int i, j;
    if(result == 1)
    {
        for(i = 0;i < *r;i++)
        {
                for(j = 0;j < *c;j++)
                {
                    if(i==j)
                        printf("%d\t",arr[j][i]);
                    else
                        printf("\t");
                }
                printf("\n");
            }
    }

    else
    {
         printf("\nMatrix is not a Square Matrix.");
    }
    return 0;
}

Answer 2

以下建议的代码：

干净地编译
执行所需的功能
正确检查并处理错误
正确使用指针和取消引用指针
使用适当的水平和垂直间距，以提高可读性
避免使用“魔术”数字

现在，建议的代码：

#include <stdio.h>
#include <stdlib.h>

#define MAX_VALUES 50

void input( int arr[ MAX_VALUES ][ MAX_VALUES ], int* r, int* c );
int compute( int r, int c );

void output( int arr[ MAX_VALUES ][ MAX_VALUES ], int r, int c, int result );


int main(void)
{
    int arr_in[ MAX_VALUES ][ MAX_VALUES ];
    int r_in;
    int c_in;


    input( arr_in, &r_in, &c_in );
    int result = compute( r_in, c_in );
    output( arr_in, r_in, c_in, result );
}


void input( int arr[ MAX_VALUES ][ MAX_VALUES ], int *r, int *c )
{
    do
    {   
        printf("Enter the no. of rows, in range 1...%d inclusive\n", MAX_VALUES );
        *r = -1;
        if( scanf( "%d", r ) != 1 )
        { 
            fprintf( stderr, "scanf failed to input number of rows\n" );
            exit( EXIT_FAILURE );
        }
    } while( *r <= 1 || *r > MAX_VALUES );

    do
    {
        *c = -1;
        printf("Enter the no. of columns, in range 1...%d inclusive\n", MAX_VALUES );
        if( scanf("%d", c) != 1 )
        {
            fprintf( stderr, "scanf failed to input number of columns\n" );
            exit( EXIT_FAILURE );
        }
    } while( *c <= 1 || *c > MAX_VALUES );

    printf("Enter the elements of the matrix\n");
    for(int i = 0;i < *r;i ++)
    {
        for(int j = 0;j < *c;j++)
        {
            printf("Enter element[%d][%d]: ", i + 1, j + 1 );
            if( scanf( "%d", &arr[i][j]) != 1 )
            {
                fprintf( stderr, "scanf failed to input a data point\n" );
                exit( EXIT_FAILURE );
            }
        }
    }
}


int compute( int r, int c )
{
    return( r == c )? 1 : 0;
}


void output( int arr[ MAX_VALUES ][ MAX_VALUES ], int r, int c, int result )
{
    if( result == 1 )
    {
        for( int i = 0; i < r; i++ )
        {
            for( int j = 0; j < c; j++ )
            {
                printf( "%d\t", arr[i][j] );    
            }
            printf("\n");         
        }
    }

    else
    {
         printf("\nMatrix is not a Square Matrix.\n");
    }
}

C程序打印矩阵的对角线元素

2 个答案: