C 語言概觀

1.第一個 C 程式—Hello World

#include<stdio.h>
#include<stdlib.h>
int main(){
    printf("***************\n");
    printf("Hello world\n");
    printf("哈囉! 您好~\n");
    system("pause");
    return 0;
}

2.撰寫一個程式，使用星號印出下列圖形(如交通號誌)

#include<stdio.h>
#include<stdlib.h>
int main(){
    printf("Hello World\n"); 
    printf("哈囉! 您好~\n"); 
    printf("*********      ***        *          *\n");
    printf("*       *     *   *      ***        * *\n");
    printf("*       *    *     *    *****      *   *\n");
    printf("*       *    *     *      *       *     *\n");
    printf("*       *    *     *      *      *       *\n");
    printf("*       *    *     *      *       *     *\n");
    printf("*       *    *     *      *        *   *\n");
    printf("*       *     *   *       *         * *\n");
    printf("*********      ***        *          *\n");
    system("pause");
    return 0;
}

3. 使用八行 printf 敍述式顯示一個西洋棋的棋盤，然後嘗試用 更少的敍述顯示相同的圖案。

#include<stdio.h>
#include<stdlib.h>
int main() {
    printf("Hello World\n");
    printf("哈囉! 您好~\n"); 
    printf("With eight printf() statement:\n");
    printf("* * * * * * * *\n");
    printf(" * * * * * * * *\n");
    printf("* * * * * * * *\n");
    printf(" * * * * * * * *\n");
    printf("* * * * * * * *\n");
    printf(" * * * * * * * *\n");
    printf("* * * * * * * *\n");
    printf(" * * * * * * * *\n");
    printf("Now with one printf() statement:\n");
    printf("* * * * * * * *\n * * * * * * * *\n* * * * * * * *\n * * * * * * * *\n* * * * * * * *\n * * * * * * * *\n* * * * * * * *\n * * * * * * * *\n");
    system("pause");
    return 0;
}

4. 在 C 語言的內部，是使用整數來表示每個字元的。這一組 字元以及電腦用來對慼這組字元的整數，就稱為電腦字元集 (character set)。你可以印出代表大寫 A 的整數。例如，執行以下 敍述式 printf(“%d”, ‘A’); 寫一個 C 程式，印出代表某些大寫字 母、小寫字母、數字和特殊符號的整數。你至少要能印出代表下 列字元的整數：A B C a b c 0 1 2 3 * + / 以及空白字元

#include<stdio.h>
#include<stdlib.h>
int main() {
    printf("Hello World\n");
    printf("哈囉! 您好~\n"); 
    printf("A's integer equivalent is %d\n",'A');
    printf("B's integer equivalent is %d\n",'B');
    printf("C's integer equivalent is %d\n",'C');
    printf("D's integer equivalent is %d\n",'D');
    printf("E's integer equivalent is %d\n",'E');
    printf("F's integer equivalent is %d\n",'F');
    printf("G's integer equivalent is %d\n",'G');
    printf("H's integer equivalent is %d\n",'H');
    printf("I's integer equivalent is %d\n",'I');
    printf("J's integer equivalent is %d\n",'J');
    printf("K's integer equivalent is %d\n",'K');
    printf("L's integer equivalent is %d\n",'L');
    printf("M's integer equivalent is %d\n",'M');
    printf("N's integer equivalent is %d\n",'N');
    printf("O's integer equivalent is %d\n",'O');
    printf("P's integer equivalent is %d\n",'P');
    printf("Q's integer equivalent is %d\n",'Q');
    printf("R's integer equivalent is %d\n",'R');
    printf("S's integer equivalent is %d\n",'S');
    printf("T's integer equivalent is %d\n",'T');
    printf("U's integer equivalent is %d\n",'U');
    printf("V's integer equivalent is %d\n",'V');
    printf("W's integer equivalent is %d\n",'W');
    printf("X's integer equivalent is %d\n",'X');
    printf("Y's integer equivalent is %d\n",'Y');
    printf("Z's integer equivalent is %d\n",'Z');
    printf("['s integer equivalent is %d\n",'[');
    printf("]'s integer equivalent is %d\n",']');
    printf("^'s integer equivalent is %d\n",'^');
    printf("_'s integer equivalent is %d\n",'_');
    printf("a's integer equivalent is %d\n",'a');
    printf("b's integer equivalent is %d\n",'b');
    printf("c's integer equivalent is %d\n",'c');
    printf("d's integer equivalent is %d\n",'d');
    printf("e's integer equivalent is %d\n",'e');
    printf("f's integer equivalent is %d\n",'f');
    printf("g's integer equivalent is %d\n",'g');
    printf("h's integer equivalent is %d\n",'h');
    printf("i's integer equivalent is %d\n",'i');
    printf("j's integer equivalent is %d\n",'j');
    printf("k's integer equivalent is %d\n",'k');
    printf("l's integer equivalent is %d\n",'l');
    printf("m's integer equivalent is %d\n",'m');
    printf("n's integer equivalent is %d\n",'n');
    printf("o's integer equivalent is %d\n",'o');
    printf("p's integer equivalent is %d\n",'p');
    printf("q's integer equivalent is %d\n",'q');
    printf("r's integer equivalent is %d\n",'r');
    printf("s's integer equivalent is %d\n",'s');
    printf("t's integer equivalent is %d\n",'t');
    printf("u's integer equivalent is %d\n",'u');
    printf("v's integer equivalent is %d\n",'v');
    printf("w's integer equivalent is %d\n",'w');
    printf("x's integer equivalent is %d\n",'x');
    printf("y's integer equivalent is %d\n",'y');
    printf("z's integer equivalent is %d\n",'z');
    printf("{'s integer equivalent is %d\n",'{');
    printf("|'s integer equivalent is %d\n",'|');
    printf("}'s integer equivalent is %d\n",'}');
    printf("~'s integer equivalent is %d\n",'~');
    printf("!'s integer equivalent is %d\n",'!');
    printf("#'s integer equivalent is %d\n",'#');
    printf("$'s integer equivalent is %d\n",'$');
    printf("%'s integer equivalent is %d\n",'%');
    printf("&'s integer equivalent is %d\n",'&');
    printf("('s integer equivalent is %d\n",'(');
    printf(")'s integer equivalent is %d\n",')');
    printf("*'s integer equivalent is %d\n",'*');
    printf("+'s integer equivalent is %d\n",'+');
    printf(",'s integer equivalent is %d\n",',');
    printf("-'s integer equivalent is %d\n",'-');
    printf(".'s integer equivalent is %d\n",'.');
    printf("/'s integer equivalent is %d\n",'/');
    printf("0's integer equivalent is %d\n",'0');
    printf("1's integer equivalent is %d\n",'1');
    printf("2's integer equivalent is %d\n",'2');
    printf("3's integer equivalent is %d\n",'3');
    printf("4's integer equivalent is %d\n",'4');
    printf("5's integer equivalent is %d\n",'5');
    printf("6's integer equivalent is %d\n",'6');
    printf("7's integer equivalent is %d\n",'7');
    printf("8's integer equivalent is %d\n",'8');
    printf("9's integer equivalent is %d\n",'9');
    printf(":'s integer equivalent is %d\n",':');
    printf(";'s integer equivalent is %d\n",';');
    printf("<'s integer equivalent is %d\n",'<');
    printf(">'s integer equivalent is %d\n",'>');
    printf("?'s integer equivalent is %d\n",'?');
    printf("@'s integer equivalent is %d\n",'@');
    printf("The blank character's integer equivalent is %d\n",' ');
    system("use");
    return 0;
}

5. 王先生是在一家資訊公司上班, 他是個朝九晚五的上班族, 也就是說王先生每天都是從九點準時上班, 一直到傍晚五點鐘下 班。試問假如王先生中午時刻是不休息的, 那他一天總共要工作 多少秒。(提示: C 語言的+、-、*、/ 運算子分別代表加、減、 乘、除)

#include<stdio.h>
#include<stdlib.h>
int main(){
    printf("Hello World\n");
    printf("哈囉! 您好~\n");
    int sec;
    int min;
    int hour;
    int time;
    sec=60;
    min=60;
    hour=8;
    time=sec*min*hour;
    printf("time is number of %d\n",time);
    printf("傍晚五點換算24小時制為17:00，早上九點換算24小時制為9:00\n");
    printf("由17:00-9:00=8:00，共8小時，一小時60分鐘，一分鐘60秒\n");
    printf("8小時計算為，8*60*60=8*3600=28800秒\n");
    system("pause");
    return 0;
}

6. 假設您現在修的科目有計概、C 語言、微積分、英文、電子 學 , 試著將它們取適當的變數名稱, 並在宣告時順便給多初值, 請計算這五科的總和及平均分數為何?

#include<stdio.h>
#include<stdlib.h>
int main(int argc, char** argv) {
 
 int computer_concepts=99,
    C_language=88,
    calculus=77,
    english=66,
    electronics=55;

printf("計概=%d\nC語言=%d\n微積分=%d\n英文=%d\n電子學=%d\n",computer_concepts,C_language,calculus,english,electronics);

printf("總分:%d",computer_concepts+C_language+calculus+english+electronics);

printf("平均:%d",(computer_concepts+C_language+calculus+english+electronics)/5);
system("pause");
 return 0;
}