《C程序设计（第三版）》习题（编程题）解答(7)

printf(\}

void count(char str[]) {int i;

for (i=0;str[i]!='\\0';i++)

if ((str[i]>='a'&& str[i]<='z')||(str[i]>='A' && str[i]<='Z')) letter++;

else if (str[i]>='0' && str [i]<='9') digit++; else if (str[i]==32) space++; else

others++; }

8.10

#include #include void main() {int alphabetic(char); int longest(char []); int i;

char line[100];

printf(\ gets(line);

printf(\

for (i=longest(line);alphabetic(line[i]);i++) printf(\ printf(\}

int alphabetic(char c)

{if ((c>='a' && c<='z')||(c>='A'&&c<='z')) return(1); else return(0); }

int longest(char string[])

{int len=0,i,length=0,flag=1,place=0,point; for (i=0;i<=strlen(string);i++) if (alphabetic(string[i])) if (flag)

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{point=i; flag=0; } else

len++; else {flag=1; if (len>=length) {length=len; place=point; len=0;

}

}

return(place); }

8.11

#include #include #define N 10 char str[N];

void main()

{void sort(char []); int i,flag;

for (flag=1;flag==1;) {printf(\ scanf(\

if (strlen(str)>N)

printf(\ else flag=0; }

sort(str);

printf(\ for (i=0;i

void sort(char str[]) {int i,j;

char t;

for(j=1;j

for (i=0;(i

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if(str[i]>str[i+1]) {t=str[i]; str[i]=str[i+1]; str[i+1]=t; } }

8.12

#include #include

void main()

{float solut(float a,float b,float c,float d); float a,b,c,d;

printf(\

scanf(\ printf(\}

float solut(float a,float b,float c,float d) {float x=1,x0,f,f1; do

{x0=x;

f=((a*x0+b)*x0+c)*x0+d; f1=(3*a*x0+2*b)*x0+c; x=x0-f/f1;

}

while(fabs(x-x0)>=1e-3); return(x); }

8.14

#include #define N 10 #define M 5

float score[N][M];

float a_stu[N],a_cour[M]; int r,c;

void main() { int i,j; float h;

float s_var(void); float highest();

void input_stu(void);

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void aver_stu(void);

void aver_cour(void); input_stu(); aver_stu(); aver_cour();

printf(\ NO. cour1 cour2 cour3 cour4 cour5 aver\\n\ for(i=0;i

{printf(\ for(j=0;j

printf(\ printf(\ }

printf(\ for (j=0;j

printf(\ printf(\

h=highest();

printf(\ NO. - course -\\n\ printf(\}

void input_stu(void) {int i,j;

for (i=0;i

{printf(\ for (j=0;j

scanf(\ } }

void aver_stu(void) {int i,j; float s;

for (i=0;i

{for (j=0,s=0;j

void aver_cour(void) {int i,j; float s;

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for (j=0;j

for (i=0;i

float highest() {float high; int i,j;

high=score[0][0]; for (i=0;ihigh) {high=score[i][j]; r=i+1; c=j+1; }

return(high);

}

float s_var(void) {int i;

float sumx,sumxn; sumx=0.0; sumxn=0.0;

for (i=0;i

{sumx+=a_stu[i]*a_stu[i]; sumxn+=a_stu[i];

}

return(sumx/N-(sumxn/N)*(sumxn/N)); }

8.15

#include #include #define N 10 void main()

{void input(int [],char name[][8]); void sort(int [],char name[][8]); void search(int ,int [],char name[][8]); int num[N],number,flag=1,c; char name[N][8];

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