几个算法基础

1. 求1-N的和：

def sum1(self, sum)
    sum = 0
    val = 1
    for val in range(n - 1):
        sum += val
        val += 1

     求数组数据的和

    def sum1(self, a):
        sum = 0
        i = 0
        size = len(a)
        for i in range(size):
            sum += a[i]
            i += 1
        return sum

2. 求斐波那契数列

# 非递归
def fibs(n):
    a = [1, 1]
    for i in range(n - 2):
        a.append(a[-2] + a[-1])
    return a[n-1]

print(fibs(n = 5))

# 递归

def fibs(n):
    if n < 1:
        return 0
    elif n == 1:
        return 1
    return fibs(n - 2) + fibs(n - 1)

print(fibs(6))

3. 求最大最小值

    def maxmin(self, a):
        max = a[0]
        i = 1
        size = len(a)
        for i in range(size):
            if a[i] > max:
                max = a[i]
                i += 1
        return max

4. 为数组元素排序（将数组SCORE名次降序保存到数组RANK中）

class Solution(object):
    def rank1(self, SCORE):
        size = len(SCORE)
        RANK = [1, 1, 1, 1, 1]
        i = 0
        for i in range(0, size):
            j = 0
            for j in range(0, size):
                if SCORE[i] < SCORE[j]:
                    RANK[i] += 1
                    j += 1
            i += 1
        return RANK

5. 二维数组的操作(求二维数组不同行的总和)

class Solution(object):
    def dyadic_array(self, SCORE):
        i = 0
        n = len(SCORE)
        for i in range(0, n):
            SCORE[i][3] = 0
            j= 0
            while j < 3:
                SCORE[i][3] += SCORE[i][j]
                j += 1
            print(SCORE[i][3])
            i += 1

if __name__ == "__main__":
    s = Solution()
    print(s.dyadic_array(SCORE = [[11, 12, 13, 0], [21, 22, 23, 0], [31, 32, 33, 0]]))

6. 欧几里得互除法&辗转相除法（求两数最大公约数）

class Solution(object):
    def dyadic_array(self, X, Y):
        R = X % Y
        while R != 0:
            X = Y
            Y = R
            R = X % Y
        GCD = Y
        print(GCD)