《Programming Abstractions In C》學(xué)習(xí)第61天，p184-p195總結(jié)。

一、技術(shù)總結(jié)

1.mutual recursion

2.natural number

(1)定義

p184, If you limit the domain of possible values to the set of natural numbers,which are defined simply as the set of nonnegative integers.

3.最大公約數(shù)

/*
 * p191. 3. The greatest common divisor(g.c.d) of two nonnegative integers is the
 * largest integer that divides evenly into both. In the third century B.C., the
 * Greek mathematician Euclid discovered that the greatest common divisor of x
 * and y can always be computed as follows:
 *
 * If x is evenly divisible by y, then y is the greatest common divisor.
 * Otherwise, the greatest common divisor of x and y is always equal to the
 * greatest common divisor of y and the remainder of x divided by y.
 *
 * Use Euclid insight to write a recursive function GCD(X, Y) that computes the
 * greatest common divisor x and y.
 */
#include <stdio.h>

int gcd(int x, int y);

/*
 * function: gcd
 * Usage: int(x, y)
 * ------------
 */
int gcd(int x, int y) {
    if (x % y == 0) {
        return y;
    }
    return gcd(y, x % y);
}


int main() {
    int result;
    result = gcd(16, 28);
    printf("GCD=%d\n", result);  // GCD=4
    return 0;
}

二、英語總結(jié)

1.holistic是什么意思？

答：

(1)holistic: holism + -istic。adj. treat the whole of sth and not just a part(整體的)。

(2)holism: holos("whole"，來自于“*sole”，完整的) + -ism(word-forming element making nouns implying a practice, system, doctrine, etc. 構(gòu)成詞的元素，暗示實(shí)踐、制度、學(xué)說等)。u. the belief that each thing is a whole that is more important the parts that make it up，整體論。

(3)-istic: adjectival word-forming element(構(gòu)成形容詞的元素)。

(4)示例：p185, Maintain a holistic perspective(保持整體的觀點(diǎn))。

2.philosophical是什么意思?

(1)philosophical: philosophy + -ical。adj. relating to the study of philosophy(哲學(xué)的)。

(2)philosophy: philo-("loving") + sophia("knowledge, wisdom")，哲學(xué)。

3.devote是什么意思？

答：de-(down from，away from, 離開) + vow(to vow“make a promise to do sth, 發(fā)誓”)，即as if by vow。

(1) vt. to use sth for a particular purpose（使用）。p185，In Chapter 2 of The Art and Science of C, I devote one section to the philosophical concepts of holism and reductionnism(在《在C語言的科學(xué)與藝術(shù)》第二章，我專門用一節(jié)來介紹整體論與還原論這兩個(gè)哲學(xué)概念。)

4.odds are good是什么意思？

答：

(1)odds: n. the probalility that a particular thing will or will not happend(可能性)。

(2)odds are good: There is a high probability that it will happen(可能性很大)。

(3)示例：p185,After all, when you write a program, the odds are good--even if you are an experienced programmer--that your program won't work the first time。

三、參考資料

1. 編程

(1)Eric S.Roberts，《Programming Abstractions in C》：https://book.douban.com/subject/2003414

2. 英語

(1)Etymology Dictionary：https://www.etymonline.com

(2) Cambridage Dictionary：https://dictionary.cambridge.org

歡迎搜索及關(guān)注：編程人(a_codists)