N=

#声明2x2的数组arr并将所有元素赋值为 None

arr=[[None] * N for row in range(N)]

print('|a1 b1|')

print('|a2 b2|')

arr[][]=input('请输入a1:')

arr[][]=input('请输入b1:')

arr[][]=input('请输入a2:')

arr[][]=input('请输入b2:')

#求二阶行列式的值

result = int(arr[][])*int(arr[][])-int(arr[][])*int(arr[][])

print('|%d %d|' %(int(arr[][]),int(arr[][])))

print('|%d %d|' %(int(arr[][]),int(arr[][])))

print('行列式值=%d' %result)

.py =====

|a1 b1|

|a2 b2|

请输入a1:

请输入b1:

请输入a2:

请输入b2:

| |

| |

行列式值=