& & a a * * ptr p int a ; int a ; int a ; int a int a

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1 int a = 123; a 123 :100 a 123 int *ptr = & a; a ptr ptr a 100 a *ptr 200 a

2 & & a a * * ptr p int a ; int *a ; int a ; int a int *a ; a a int int *pc ; pc = &a ; int a ; a = 20; 345 *pc a 20

3 ⅱ int pc int a pc a int a ; int *pc ; pc a pc = &a ; pc a int pc int a pc * *pc a *pc a *pc a #include<stdio.h> int main() { int a,b; int *pc; a = 25; printf(" a :%x(16 \n\n",&a); printf(" b :%x(16 \n\n",&b); printf(" a :%d 10 \n\n",a); puts(" \n"); pc = &a; b = *pc + 100; *pc = 6; puts("pc = &a\n" "b = *pc +100\n" "*pc =6\n" " \n"); printf(" pc :%x(16 \n\n",pc); printf(" b :%d 10 \n\n",b); printf(" a :%d 10 \n\n",a); return 0;

4 a :5fbffacc(16 b :5fbffac8 16 a : pc = &a b = *pc +100 *pc =6 pc b a :5fbffacc 16 : : & a pc a *pc a 21 pc pc a b b *pc +100 a a *pc =a a 8

5 /* */ #include<stdio.h> #include<ctype.h> void replace(char *dest,char *str); int main(int argc,char **argv){ char dest[256]={0; int i; printf(" :%d\n\n",argc); for(i=1; i<argc; i++){ replace(dest, argv[i]); // argv[i] == *(argv + i) printf(" : %s\n : %s\n\n",argv[i],dest); return 0; void replace(char *dest,char *str){ int i; for(i=0; str[i]!= NULL; i++){ if(isalpha(str[i])){ if(isupper(str[i])) dest[i] = tolower(str[i]); else dest[i] = toupper(str[i]); else dest[i] = str[i]; dest[i] = NULL;

6 Yukihiro-Ikehara-no-MacBook-Pro:prog1 e105746$./a.out Abc DeTrmInaNt. :4 : Abc : abc : DeTrmInaNt : detrminant :. :. i 4 ctype.h isalpha,isupper,tolwer,toupper 6 void replace char *dest, *str 8 19 int main int argc char argv main 2 9 char dest argc argc main for i 1 i argc i replace dest argv[i] 17 dest argv[i] replace void str for

7 ./a.out Abc DeTrmInaNt. argc argv argv[] argv argv[0]. / a. o u t NULL argv[1] A b c NULL argv[2] D e T r m I n a N t NULL argv[3]. NULL 1 replace argv[0] 2 argv[1]... n argv[n] argv [] NULL 3 replace replace main *dest,*str *str 1 dest NULL main main for i 0./a.out

8 /* */ #include<stdio.h> void reverse(char *dest,char *str); int main(int argc,char **argv){ char dest[256]={0; int i; printf(" :%d\n\n",argc); for(i=1; i<argc; i++){ reverse(dest, argv[i]); printf(" : %s\n : %s\n\n",argv[i],dest); return 0; void reverse(char *dest,char *str){ int i,kiri; for(kiri = 0; str[kiri]!= NULL; kiri++); for(i=0; i<kiri; i++) dest[i]=str[kiri-i-1]; dest[i]=null;

9 Yukihiro-Ikehara-no-MacBook-Pro:prog1 e105746$./a.out God of eater. :5 : God : dog : of : fo : eater : retae :. :. < main reverse reverse 20 char *dest *str 14 dest argv[i] for 22 reverse int i,kiri 24 for argv[i] kiri Kiri argv[i] argv[i] God kiri argv[i] kiri dest[0] = str[2] dest[1] = str[1] dest[2] = str[0] dest argv[i]

10 28 dest[i] argv[i] reverse dest str main reverse argv[1] str[0] str[1] str[2] G o d dest[0] dest[1] dest[2] d o G argv[2] str[0] str[1] o f dest[0] dest[1] f o argv[3] str[0] str[1] str[2] str[3] str[4] e a t e r

11 argv[3] dest[0] dest[1] dest[2] dest[3] dest[4] r e t a e

12 #include<stdio.h> void reverse(char *dest,char *str); int main(int argc,char **argv){ char dest[256]={0; int i; printf(" :%d\n\n",argc); for(i=1; i<argc; i++){ reverse(dest, argv[i]); printf(" : %s\n : %s\n\n",argv[i],dest); return 0; void reverse(char *dest,char *str){ int i,kiri; for(kiri = 0; str[kiri]!= NULL; kiri++); for(i=0; i<kiri; i++) dest[i]=str[kiri-i-1]; Yukihiro-Ikehara-no-MacBook-Pro:prog1 e105746$./a.out God of eater :4 : God : dog : of : fog : eater : retae reverse dest[i] = NULL; of G

13 reverse argv[1] str[0] str[1] str[2] G o d dest[0] dest[1] dest[2] d o G argv[2] str[0] str[1] o f G arg1 G f o G arg[3] arg[2] C

コマンドラインから受け取った文字列の大文字と小文字を変換するプログラムを作成せよ入力は 1 バイトの表示文字としアルファベット文字以外は変換しない 1. #include <stdio.h> 2. #include <ctype.h> /*troupper,islower,isupper,tol

コマンドラインから受け取った文字列の大文字と小文字を変換するプログラムを作成せよ入力は 1 バイトの表示文字としアルファベット文字以外は変換しない 1. #include 2. #include /*troupper,islower,isupper,tolowerを使うため宣言*/ 3. 4. int get_n(char *); 5. void replace(char