C语言课后习题8.docx

1、C语言课后习题88.1hcf(u,v)int u,v;int a,b,t,r;if(uv)t=u;u=v;v=t;a=u;b=v;while(r=b%a)!=0) b=a;a=r;return(a);lcd(u,v,h)int u,v,h;return(u*v/h);main()int u,v,h,l;scanf(%d,%d,&u,&v);h=hcf(u,v);printf(H.C.F=%dn,h);l=lcd(u,v,h);printf(L.C.D=%dn,l);8.2#includemath.hfloat x1,x2,disc,p,q;greater_than_zero(a,b)float

2、 a,b;x1=(-b+sqrt(disc)/(2*a);x2=(-b-sqrt(disc)/(2*a);equal_to_zero(a,b)flaot a,b;x1=x2=-b/(2*a);smaller_than_zero(a,b)float a,b;p=-b/(2*a);q=sqrt(-disc)/(2*a);main()float a,b,c;scanf(%f,%f,%f,&a,&b,&c);disc=b*b-4*a*c;if(fabs(disc)0) greater_than_zero(a,b); printf(x1=%5.2ftx2=%5.2fn,x1,x2); else smal

3、ler_than_zero(a,b); printf(x1=%5.2f+%5.2fitx2=%5.2f-%5.2fin,p,q,p,q); 8.3main()int number;scanf(%d,&number);if(prime(number) printf(yes);else printf(no);int prime(number)int number;int flag=1,n;for(n=2;nnumber/2&flag=1;n+) if(number%n=0) flag=0;return(flag);8.4#define N 3int arrayNN;convert(array)in

4、t array33;int i,j,t;for(i=0;iN;i+) for(j=i+1;jN;j+) t=arrayij; arrayij=arrayji; arrayji=t; main()int i,j;for(i=0;iN;i+)for(j=0;jN;j+) scanf(%d,&arrayij);convert(array);for(i=0;iN;i+) printf(n); for(j=0;jN;j+) printf(%5d,arrayij); 8.5main()char str100;scanf(%s,str);inverse(str);printf(%sn,str);invers

5、e(str)char str;char t;int i,j;for(i=0,j=strlen(str);i0;i-) stri*2=stri; stri*2-1= ; printf(%sn,str);8.9int alph,digit,space,others;main()char text80;gets(text);alph=0,digit=0,space=0,others=0;count(text);printf(nalph=%d,digit=%d,space=%d,others=%dn,alph,digit,space,others);count(str)char str;int i;f

6、or(i=0;stri!=0;i+) if(stri=a&stri=A&stri=0&striN) printf(input error); else flag=0; sort(str);for(i=0;iN;i+) printf(%c,stri);sort(str)char strN;int i,j;char t;for(j=1;jN;j+) for(i=0;(istri+1) t=stri; stri=stri+1; stri+1=t; 8.13main()int x,n;float p();scanf(%d,%d,&n,&x);printf(P%d(%d)=%10.2fn,n,x,p(n

7、,x);float p(tn,tx)int tn,tx;if(tn=0) return(1);else if(tn=1) return(tx);else return(2*tn-1)*tx*p(tn-1),tx)-(tn-1)*p(tn-2),tx)/tn);8.14#define N 10#define M 5float scoreNM;float a_stuN,a_corM;main()int i,j,r,c;float h;float s_diff();float highest();r=0;c=1;input_stu();avr_stu();avr_cor();printf(n num

8、ber class 1 2 3 4 5 avr);for(i=0;iN;i+) printf(nNO%2d,i+1); for(j=0;jM;j+) printf(%8.2f,scoreij); printf(%8.2f,a_stui); printf(nclassavr);for(j=0;jM;j+) printf(%8.2f,a_corj);h=highest(&r,&c);printf(nn%8.2f %d %dn,h,r,c);printf(n %8.2fn,s_diff();input_stu()int i,j;float x;for(i=0;iN;i+) for(j=0;jM;j+

9、) scanf(%f,&x); scoreij=x; avr_stu()int i,j;float s;for(i=0;iN;i+) for(j=0,s=0;jM;j+) s+=scoreij; a_stui=s/5.0; avr_cor()int i,j;float s;for(j=0;jM;j+) for(i=0,s=0;iN;i+) s+=scoreij; a_corj=s/(float)N; float highest(r,c)int *r,*c;float high;int i,j;high=score00;for(i=0;iN;i+) for(j=0;jhigh) high=sco

10、reij; *r=i+1; *c=j+1; return(high);float s_diff()int i,j;float sumx=0.0,sumxn=0.0;for(i=0;iN;i+) sumx+=a_stui*a_stui; sumxn+=a_stui; return(sumx/N-(sumxn/N)*(sumxn/N);8.17#includevoid convert(n)int n;int i;if(i=n/10)!=0) convert(i);putchar(n%10+0);main()int number;scanf(%d,&number);if(number=3) days+=1;printf(days=%dn,days);static int day_tab13=0,31,28,31,30,31,30,31,31,30,31,30,31int sum_day(month,day)int month,day;int i;for(i=1;imonth;i+) day+=day_tabi;return(day);int leap(year)int year;int leap;leap=year%4=0&year%100!=0|year%400=0;return(leap);