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Array Mathematics | HackerRank

 

문제

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Task

You are given two integer arrays, A and B of dimensions N X.M
Your task is to perform the following operations:

1. Add (A + B)
2. Subtract (A - B)
3. Multiply (A * B)
4. Integer Division (A / B)
5. Mod (A % B)
6. Power (A ** B)

Note
There is a method numpy.floor_divide() that works like numpy.divide() except it performs a floor division.

Input Format

The first line contains two space separated integers, N and M.
The next N lines contains M space separated integers of array A.
The following N lines contains M space separated integers of array B.

Output Format

 

Print the result of each operation in the given order under Task.

 

=> array A,B 에 들어갈 M개의 숫자들을 N줄 줄건데 A,B에 대해 Task를 실행하라

 

 

 

 

코드

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import numpy as np

N, M = map(int, input().split())


A = np.array([list(input().split()) for _ in range(N)], int)
B = np.array([list(input().split()) for _ in range(N)], int)

print(A + B)
print(A - B)
print(A * B)
print(np.floor_divide(A,B))  # A//B 나눗셈에서 몫을 구하는 메소드
print(A % B)
print(A ** B)

 

 

 

 

노트

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array의 연산

import numpy

a = numpy.array([1,2,3,4], float)
b = numpy.array([5,6,7,8], float)

# 더하기
print(a + b)                     #[  6.   8.  10.  12.]
print(numpy.add(a, b))           #[  6.   8.  10.  12.]

# 빼기
print(a - b)                     #[-4. -4. -4. -4.]
print(numpy.subtract(a, b))      #[-4. -4. -4. -4.]

# 곱하기
print(a * b)                     #[  5.  12.  21.  32.]
print(numpy.multiply(a, b))      #[  5.  12.  21.  32.]

# 나누기
print(a / b)                     #[ 0.2         0.33333333  0.42857143  0.5       ]
print(numpy.divide(a, b))        #[ 0.2         0.33333333  0.42857143  0.5       ]

# 나눗셈의 몫
print(a // b)                    #[0. 0. 0. 0.]
print(numpy.floor_divide(a,b))   #[0. 0. 0. 0.]

# 나눗셈의 나머지
print(a % b)                     #[ 1.  2.  3.  4.]
print(numpy.mod(a, b))           #[ 1.  2.  3.  4.]

# 거듭제곱
print(a**b)                      #[  1.00000000e+00   6.40000000e+01   2.18700000e+03   6.55360000e+04]
print(numpy.power(a, b))         #[  1.00000000e+00   6.40000000e+01   2.18700000e+03   6.55360000e+04]

• 같은 인덱스끼리 연산됨
• 같은 shape여야만 연산이 가능함

 

 

 

 

참조

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기본 수학 함수 | Numpy.floor_divide