c - 为什么我的代码跳过整个 for 循环？

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我仍在学习 C 的基础知识，并且我的任务是编写一个程序，该程序显示用户输入的两个 2D 数组的乘积。这个想法是不使用像 malloc 这样的内存函数。

代码工作正常，但是当我添加 if 语句来检查运行时第一个数组的行是否等于下一个数组的列时，用于输入第一个数组的数据并显示的整个部分它被跳过并直接询问下一个数组。我尝试清理缓冲区并使用 getch() 尝试强制编译器执行该部分，但它一直被跳过。

这是完整的代码:

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <conio.h>
int main(void);
int main (void)
#define MAXR 36
#define MAXC 18 
{
    int Rows_A,Columns_A,Rows_B,Columns_B,Rows_C,Columns_C;
int Counter_Rows=0,Counter_Columns=0,Counter_Multiplier=0;
int Matrix_A[MAXR][MAXC],Matrix_B[MAXR][MAXC],Results_Matrix_C[MAXR][MAXC];
printf("\n\tTo multiply two matrices both have to be the same size of rows from the first matrix and the columns from the next one. \n\tPlease enter the size of the matrices:\n");

printf("\n\tMatrix A:\n\tNumber of rows :\t\t");
scanf(" %d",&Rows_A);
printf("\n\tNumber of columns :\t\t");
scanf(" %d",&Columns_A);
printf("\n\tMatrix B:\n\tNumber of rows :\t\t");
fflush(stdin);
scanf(" %d",&Rows_B);
printf("\n\tNumber of columns :\t\t");
scanf(" %d",&Columns_B);
if (Rows_A=!Columns_B)
{
    printf("\n\tMatrix B number of columns and Matrix A number of rows are not the same therefore they cannot be multiplied.");
    return 0;
}
else
{
    Rows_C=Rows_A;
    Columns_C=Columns_B;
    printf("\n\tEnter the data for Matrix A:");
    for (Counter_Rows=0;Counter_Rows < Rows_A;Counter_Rows++)
    {   
        for(Counter_Columns=0;Counter_Columns < Columns_A; Counter_Columns++)
        {
            printf("\n\tEnter the value of the position [%d][%d] of the matrix A:  ",Counter_Rows+1,Counter_Columns+1);
            scanf(" %d",&Matrix_A[Counter_Rows][Counter_Columns]);
        }
    }
    printf("\n\tMatrix A.\n\t");//Matrix A
    for (Counter_Rows= 0; Counter_Rows < Rows_A; Counter_Rows++)
    {
        for (Counter_Columns= 0; Counter_Columns < Columns_A; Counter_Columns++)
        {
            printf("[%d] ",Matrix_A[Counter_Rows][Counter_Columns]);
        }
        printf("\n\t");
    }
    fflush(stdin);
    printf("\n\tEnter the data for Matrix B:");
    for (Counter_Rows=0;Counter_Rows < Rows_B;Counter_Rows++)
    {
        for(Counter_Columns=0;Counter_Columns < Columns_B; Counter_Columns++)
        {
            printf("\n\tEnter the value of the position [%d][%d] of the matrix B:  ",Counter_Rows+1,Counter_Columns+1);
            scanf(" %d",&Matrix_B[Counter_Rows][Counter_Columns]);
        }
    }
    printf("\n\tMatrix B.\n\t");//Matrix B.
    for (Counter_Rows= 0; Counter_Rows < Rows_B; Counter_Rows++)
    {
        for (Counter_Columns= 0; Counter_Columns < Columns_B; Counter_Columns++)
        {
            printf("[%d] ",Matrix_B[Counter_Rows][Counter_Columns]);
        }
        printf("\n\t");
    }
    //Calculating product matrix C.
    for (Counter_Rows=0;Counter_Rows < Rows_C;Counter_Rows++)
    {
        for(Counter_Columns=0;Counter_Columns < Columns_C; Counter_Columns++)
        {
            //initializes the Matrix  C in 0's
            Results_Matrix_C[Counter_Rows][Counter_Columns]=0;
            for(Counter_Multiplier=0; Counter_Multiplier < Columns_A; Counter_Multiplier++)
            {
                Results_Matrix_C[Counter_Rows][Counter_Columns]=Results_Matrix_C[Counter_Rows][Counter_Columns]+(Matrix_A[Counter_Rows][Counter_Multiplier]*Matrix_B[Counter_Multiplier][Counter_Columns]);
            }
        }
    }
    printf("\n\tProduct Matrix C:\n\t");//Matrix B.
    for (Counter_Rows= 0; Counter_Rows < Rows_C; Counter_Rows++)
    {
        for (Counter_Columns= 0; Counter_Columns < Columns_C; Counter_Columns++)
        {
            printf("[%d] ",Results_Matrix_C[Counter_Rows][Counter_Columns]);
        }
        printf("\n\t");
    }
}
return 0;

}

这是被跳过的部分:

printf("\n\tEnter the data for Matrix A:");
    for (Counter_Rows=0;Counter_Rows < Rows_A;Counter_Rows++)
    {   
        for(Counter_Columns=0;Counter_Columns < Columns_A; Counter_Columns++)
        {
            printf("\n\tEnter the value of the position [%d][%d] of the matrix A:  ",Counter_Rows+1,Counter_Columns+1);
            scanf(" %d",&Matrix_A[Counter_Rows][Counter_Columns]);
        }
    }
    printf("\n\tMatrix A.\n\t");//Matrix A
    for (Counter_Rows= 0; Counter_Rows < Rows_A; Counter_Rows++)
    {
        for (Counter_Columns= 0; Counter_Columns < Columns_A; Counter_Columns++)
        {
            printf("[%d] ",Matrix_A[Counter_Rows][Counter_Columns]);
        }
        printf("\n\t");
    }

Answer 1

您的示例中有 if (Rows_A=!Columns_B) 。我认为你想要 if (Rows_A != Columns_B)