c答案(7)

flag=0; } } 7.16

＃i nclude #define MAX 1000 main()

{int c,i,flag,flag1; char t[MAX]; i=0; flag=0;

flag1=1;

while((c=getchar())!='\\0'&&i

{if(c>='0'&&c<='9'||c>='A'&&c<='F'||c>='a'&&c<='f') {flag=1; t[i++]=c; }

else if(flag) {t[i]='\\0';

printf(\ printf(\ c=getchar(); if(c=='n'||c=='N') flag1=0; else

{flag=0; i=0; } } } } htoi(s) char s[]; {int i,n; n=0;

for(i=0;s[i]!='\\0';i++) {if(s[i]>='0'&&s[i]<='9') n=n*16+s[i]-'0'; if(s[i]>='a'&&s[i]<='f') n=n*16+s[i]-'a'+10; if(s[i]>='A'&&s[i]<='F') n=n*16+s[i]-'A'+10; }

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return(n); } 7.17

＃i nclude void convert(n) int n;

{int i;

if((i=n/10)!=0) convert(i); putchar(n+'0'); }

main()

{int number;

scanf(\ if(number<0) {putchar('-');

number=-number; }

convert(number); }

7.18 main()

{int year,month,day;

int days;

scanf(\ days=sum_day(month,day); if(leap(year)&&(month>=3)) days+=1;

printf(\}

static int day_tab[13]={0,31,28,31,30,31,30,31,31,30,31,30,31} int sum_day(month,day) int month,day; {int i;

for(i=1;i

int leap(year)

int year; {int leap;

leap=year%4==0&&year0!=0||year@0==0;

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return(leap); }

第八章 编译预处理 8.1

#define SWAP(a,b) t=b;b=a;a=t main()

{int a,b,t;

scanf(\ SWAP(a,b);

printf(\} 8.2

#define SURPLUS(a,b) ((a)%(b)) main()

{int a,b;

scanf(\

printf(\}

8.3

＃i nclude\

#define S(a,b,c) ((a+b+c)/2)

#define AREA(a,b,c) (sqrt(S(a,b,c)*(S(a,b,c)-a)*(S(a,b,c)-b)*(S(a,b,c)-c))) main()

{float a,b,c;

scanf(\ if(a+b>c&&b+c>a&&a+c>b)

printf(\ else

printf(\}

8.4

#define LEAP(y) (y%4==0)&&(y0!=0)||(y@0==0) main()

{int year;

scanf(\ if(LEAP(year)) printf(\ else

printf(\}

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8.5

printf(\

printf(\

printf(\输出结果：

value=5.000000ormat \value=3.000000ormat \ 8.6

\#define NL \#define Fs \#define F \#define F1 F NL

#define F2 F \#define F3 F \main()

{float a,b,c; scanf(Fs,&a); scanf(Fs,&b); scanf(Fs,&c); PR(NL); PR(F1,a); PR(F1,b); PR(F1,c); PR(NL); PR(F2,a,b); PR(F1,c); PR(NL); PR(F3,a,b,c); }

8.7

/*format.h文件*/

#define DIGIT(d) printf(\#define FLOAT(f) printf(\#define STRING(s) printf(\/*用户文件*/ ＃i nclude\main() {int d,num; float f; char s[80];

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scanf(\ switch(num)

{case 1:scanf(\ DIGIT(d); break; case 2:scanf(\ FLOAT(f); break;

case 3:scanf(\ STRING(s); break;

default:printf(\ } } 8.8

main() {int a,b,c;

scanf(\ printf(\}

max(a,b,c) int a,b,c; {int t;

t=x>y?x:y; return(t>z?t:z); }

#define MAX(a,b) ((a)>(b)?(a):(b)) main()

{int a,b,c;

scanf(\ printf(\}

8.10

＃i nclude\#define MAX 80 #define CHANGE 1 main()

{char str[MAX]; int i;

scanf(\ #if(CHANGE)

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