C高级-day(2)

代码：

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <pthread.h>
#include <semaphore.h>
#include <stdlib.h>

int main(int argc, const char *argv[])
{
    // 行列初始化
    int n = 0, m = 0;
    printf("请输入行:");
    scanf("%d", &n);
    printf("请输入列:");
    scanf("%d", &m);
    int A[n][m];
    int X[n][m];

    // 循环输入数组数据
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            printf("A[%d][%d]:", i, j);
            scanf("%d", &A[i][j]);
        }
    }

    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            printf("%d\t", A[i][j]);
        }
        printf("\n");
    }

    int sum;

    for (int i = 0; i < n; i++)
    {

        for (int j = 0; j < m; j++)
        {
            sum = 1;

            for (int row = 0; row < n; row++)
            {
                if (row != i)
                {
                     //printf("row = %d  i = %d\n", row, i);
                    sum *= A[row][j];
                }
               
            }

            for (int line = 0; line < m; line++)
            {
                if (line != j)
                {
                    sum *= A[i][line];
                }
                
            }

            X[i][j] = sum;
            printf("%d\t", sum);
        }

        printf("\n");
    }

    int max = 0;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (i == 0 && j == 0)
            {
                max = X[i][j];
            }

            if (max < X[i][j])
            {
                max = X[i][j];
            }
        }
    }

    printf("最大值是:%d", max);

    return 0;
}

结果：

2.有一个unsigned char类型的数据data，把他的第六个bit位置为1。请写出将 data第6位清0的表达式

 答：表达式:data &= ~(1 << 5)

                       data |= (1<<5)