C PRIMER PLUS 第七八正确答案.docx
《C PRIMER PLUS 第七八正确答案.docx》由会员分享，可在线阅读，更多相关《C PRIMER PLUS 第七八正确答案.docx（22页珍藏版）》请在冰豆网上搜索。
CPRIMERPLUS第七八正确答案
Chapter7
PE7-1
#include
intmain（void）
{
charch;
intsp_c,re_c,oc_c;
sp_c=re_c=oc_c=0;
printf（"inuputastring,andthisprogramwilloutthecountof...\n"）;
while（（ch=getchar（））!
='#'）
{
if（'\n'==ch）
re_c++;
elseif（''==ch）
sp_c++;
else
oc_c++;
}
printf（"%d%s,%d%s,%d%s",re_c+1,"newlines",sp_c,"spaces",oc_c,"othercharacters\n"）;
printf（"Bye!
\n"）;
return0;
}
PE7-2
#include
intmain（void）
{
charch;
intcount=0;
printf（"inuputastring,andthisprogramwilloutitandASCII\n（#toquit）...\n"）;
while（（ch=getchar（））!
='#'）
{
if（ch=='\n'）{
printf（"\ninputanotherstring（#toquit）:
\n"）;
continue;
}
while（count==8）{
printf（"\n"）;
count=0;
}
printf（"%c,%d",ch,ch）;
count++;
}
printf（"\nBye!
\n"）;
return0;
}
PE7-3
#include
intmain（void）
{
intn;
doublesumeven=0.0;
intct_even=0;
doublesumodd=0.0;
intct_odd=0;
while（scanf（"%d",&n）==1&&n!
=0）
{
if（n%2==1）
{
sumodd+=n;
++ct_odd;
}
else
{
sumeven+=n;
++ct_even;
}
}
printf（"Numberofevens:
%d",ct_even）;
if（ct_even>0）
printf（"average:
%g",sumeven/ct_even）;
putchar（'\n'）;
printf（"Numberofodds:
%d",ct_odd）;
if（ct_odd>0）
printf（"average:
%g",sumodd/ct_odd）;
putchar（'\n'）;
printf（"\ndone\n"）;
return0;
}
PE7-4
#include
intmain（void）
{
charch;
intex_c,pe_c;
ex_c=pe_c=0;
printf（"inuputastring,andthisprogramwillswitch.to!
and!
to!
!
\n（#toquit）...\n"）;
while（（ch=getchar（））!
='#'）
{
if（ch=='.'）{
printf（"!
"）;
pe_c++;
continue;
}
elseif（ch=='!
'）{
printf（"!
!
"）;
ex_c++;
continue;
}
printf（"%c",ch）;
}
printf（"\nthereare%dpeswitchingand%dexswitching",pe_c,ex_c）;
printf（"\nBye!
\n"）;
return0;
}
PE7-5
#include
intmain（void）
{
charch;
intct1=0;
intct2=0;
printf（"inuputastring,andthisprogramwillswitch.to!
and!
to!
!
\n（#toquit）...\n"）;
while（（ch=getchar（））!
='#'）
{
switch（ch）
{
case'.':
putchar（'!
'）;
++ct1;
break;
case'!
':
putchar（'!
'）;
putchar（'!
'）;
++ct2;
break;
default:
putchar（ch）;
}
}
printf（"%dreplacementsof.with!
\n",ct1）;
printf（"%dreplacementsof!
with!
!
\n",ct2）;
return0;
}
PE7-6
#include
intmain（void）{
charch;
inte_c,i_c,st_c;
e_c=i_c=st_c=0;
printf（"inputyourstringandthisprogramwilloutputthecount\n（#toquit）:
\n"）;
while（（ch=getchar（））!
='#'）{//当输入ei时st_c=10,i_c=10
if（ch!
='i'）{//当输入ie时st_c=10,i_c=1,输入其他字符st_c=2
st_c=2;
if（ch=='e'）{
st_c=10;
i_c=1;
}
}
if（ch=='i'）
i_c=10;
if（st_c==i_c）{//防止eii的bug
e_c++;
st_c=1;
}
}
printf（"\nthereis%deiinyourstring!
\nbye!
\n",e_c）;
return0;
}
PE7-7
#include
#defineBASEPAY10/*$10perhour*/
#defineBASEHRS40/*hoursatbasepay*/
#defineOVERTIME1.5/*1.5time*/
#defineAMT1300/*1stratetier*/
#defineAMT2150/*2stratetier*/
#defineRATE10.15/*ratefor1sttier*/
#defineRATE20.20/*ratefor2ndtier*/
#defineRATE30.25/*ratefor3rdtier*/
intmain（void）
{
doublehours;
doublegross;
doublenet;
doubletaxes;
printf（"Enterthenumberofhoursworkedthisweek:
"）;
scanf（"%lf",&hours）;
if（hours<=BASEHRS）
gross=hours*BASEPAY;
else
gross=BASEHRS*BASEPAY+（hours-BASEHRS）*BASEPAY*OVERTIME;
if（gross<=AMT1）
taxes=gross*RATE1;
elseif（gross<=AMT1+AMT2）
taxes=AMT1*RATE1+（gross-AMT1）*RATE2;
else
taxes=AMT1*RATE1+AMT2*RATE2+（gross-AMT1-AMT2）*RATE3;
net=gross-taxes;
printf（"gross:
$%.2f;taxes:
$%.2f;net:
$%.2f\n",gross,taxes,net）;
return0;
}
PE7-8
#include
#include
#defineBASEPAY10/*$10perhour*/
#defineBASEHRS40/*hoursatbasepay*/
#defineOVERTIME1.5/*1.5time*/
#defineAMT1300/*1stratetier*/
#defineAMT2150/*2stratetier*/
#defineRATE10.15/*ratefor1sttier*/
#defineRATE20.20/*ratefor2ndtier*/
#defineRATE30.25/*ratefor3rdtier*/
intmain（void）{
doublehours;
doublegross;
doublenet;
doubletaxes;
intchoose;inttest=1;
printf（"*****************************************************************\n"）;
printf（"Enterthenumbercorrespondingtothedesiredpayrateoraction:
\n"）;
printf（"1）$8.75/hr\t\t2）$9.33/hr\n3）$10.00/hr\t\t4）$11.20/hr\n5）quit\n"）;
printf（"*****************************************************************\n"）;
printf（"Enterthenumberofhoursworkedthisweek:
"）;
while（（scanf（"%d",&choose））==1）{
switch（choose）{
case1:
hours=8.75;
break;
case2:
hours=9.33;
break;
case3:
hours=10.00;
break;
case4:
hours=11.20;
break;
case5:
test=0;
break;
default:
test=2;
printf（"error!
tryagain:
\n"）;
break;
}
if（test==2）{
test=1;
continue;
}
if（test==1）{
if（hours<=BASEHRS）
gross=hours*BASEPAY;
else
gross=BASEHRS*BASEPAY+（hours-BASEHRS）*BASEPAY*OVERTIME;
if（gross<=AMT1）
taxes=gross*RATE1;
elseif（gross<=AMT1+AMT2）
taxes=AMT1*RATE1+（gross-AMT1）*RATE2;
else
taxes=AMT1*RATE1+AMT2*RATE2+（gross-AMT1-AMT2）*RATE3;
net=gross-taxes;
printf（"gross:
$%.2f;taxes:
$%.2f;net:
$%.2f\nnext:
",gross,taxes,net）;
}
elseif（test==0）{
break;
}
}
printf（"Bye!
\n"）;
return0;
}
PE7-9
#include
#defineNO0
#defineYES1
intmain（void）
{
longnum;/*valuetobechecked*/
longdiv;/*potentialdivisors*/
longlim;/*limittovalues*/
intprime;
printf（"Pleaseenterlimittovaluestobechecked;"）;
printf（"Enterqtoquit.\n"）;
while（scanf（"%ld",&lim）==1&&lim>0）
{
for（num=2;num<=lim;num++）
{
for（div=2,prime=YES;（div*div）<=num;div++）
if（num%div==0）
prime=NO;/*numberisnotprime*/
if（prime==YES）
printf（"%ldisprime.\n",num）;
}
printf（"Pleaseenteranotherlimit;"）;
printf（"Enterqtoquit.\n"）;
}
return0;
}
PE7-11
#include
#include
intmain（void）
{
constdoubleprice_artichokes=1.25;
constdoubleprice_beets=0.65;
constdoubleprice_carrots=0.89;
constdoubleDISCOUNT_RATE=0.05;
charch;
doublelb_artichokes;
doublelb_beets;
doublelb_carrots;
doublelb_total;
doublecost_artichokes;
doublecost_beets;
doublecost_carrots;
doublecost_total;
doublefinal_total;
doublediscount;
doubleshipping;
printf（"Enteratobuyartichokes,bforbeets,"）;
printf（"cforcarrots,qtoquit:
"）;
while（（ch=getchar（））!
='q'&&ch!
='Q'）
{
if（ch=='\n'）
continue;
while（getchar（）!
='\n'）
continue;
ch=tolower（ch）;
switch（ch）
{
case'a':
printf（"Enterpoundsofartichokes:
"）;
scanf（"%lf",&lb_artichokes）;
break;
case'b':
printf（"Enterpoundsofbeets:
"）;
scanf（"%lf",&lb_beets）;
break;
case'c':
printf（"Enterpoundsofcarrots:
"）;
scanf（"%lf",&lb_carrots）;
break;
default:
printf（"%cisnotavalidchoice.\n"）;
}
printf（"Enteratobuyartichokes,bforbeets,"）;
printf（"cforcarrots,qtoquit:
"）;
}
cost_artichokes=price_artichokes*lb_artichokes;
cost_beets=price_beets*lb_beets;
cost_carrots=price_carrots*lb_carrots;
cost_total=cost_artichokes+cost_beets+cost_carrots;
lb_total=lb_artichokes+lb_beets+lb_carrots;
if（lb_total<=0）
shipping=0.0;
elseif（lb_total<5.0）
shipping=3.50;
elseif（lb_total<20）
shipping=10.0;
else
shipping=8.0+0.1*lb_total;
if（cost_total>100.0）
discount=DISCOUNT_RATE*cost_total;
else
discount=0.0;
final_total=cost_total+shipping-discount;
printf（"Yourorder:
\n"）;
printf（"%.2flbsofartichokesat$%.2fperpound:
$%.2f\n",
lb_artichokes,price_artichokes,cost_artichokes）;
printf（"%.2flbsofbeetsat$%.2fperpound:
$%.2f\n",
lb_beets,price_beets,cost_beets）;
printf（"%.2flbsofcarrotsat$%.2fperpound:
$%.2f\n",
lb_carrots,price_carrots,cost_carrots）;
printf（"Totalcostofvegetables:
$%.2f\n",cost_total）;
if（cost_total>100）
printf（"Volumediscount:
$%.2f\n",discount）;
printf（"Shipping:
$%.2f\n",shipping）;
printf（"Totalcharges:
$%.2f\n",final_total）;
return0;
}
Chapter8
PE8-1
//Ctrl+z结束文件
#include
intmain（void）
{
intch;
intct=0;
while（（ch=getchar（））!
=EOF）
ct++;
printf（"%dcharactersread\n",ct）;
return0;
}
PE8-3
/*ProgrammingExercise8-3*/
/*Usingctype.heliminatesneedtoassumeASCIIcoding*/
#include
#include
intmain（void）
{
intch;
intuct=0;
intlct=0;
while（（ch=getchar（））!
=EOF）
if（isupper（ch））
uct++;
elseif（islower（ch））
lct++;
printf（"%duppercasecharactersread\n",uct）;
printf（"%dlowercasecharactersread\n",lct）;
return0;
}
/*
oryoucoulduse
if（ch>='A'&&ch<='Z'）
uct++;
elseif（ch>='a'&&ch<='z'）
lct++;
*/
PE8-5
/*ProgrammingExercise8-5*/
/*binaryguess.c--animprovednumber-guesser*/
#include
#include
intmain（void）
{
inthigh=100;
intlow=1;
intguess=（high+low）/2;
charresponse;
printf（"Pickanintegerfrom1to100.Iwilltrytoguess"）;
printf（"it.\nRespondwithayifmyguessisright,with"）;
printf（"\nahifitishigh,andwithanlifitislow.\n"）;
printf（"Uh...isyournumber
升级会员 