谁有C++程序设计的习题答案??

第一章
1.6
main()
{int a,b,c,max;
printf("input three numbers:\n");
scanf("%d,%d,%d",&a,&b,&c);
max=a;
if(maxif(maxprintf("max=%d",max);
}

第二章
2.3
(1)(10)10=(12)8=(a)16
(2)(32)10=(40)8=(20)16
(3)(75)10=(113)8=(4b)16
(4)(-617)10=(176627)8=(fd97)16
(5)(-111)10=(177621)8=(ff91)16
(6)(2483)10=(4663)8=(963)16
(7)(-28654)10=(110022)8=(9012)16
(8)(21003)10=(51013)8=(520b)16

2.6
aabb (8)cc (8)abc
(7)AN

2.7
main()
{char c1='C',c2='h',c3='i',c4='n',c5='a';
c1+=4, c2+=4, c3+=4, c4+=4, c5+=4;
printf("%c%c%c%c%c\n",c1,c2,c3,c4,c5);
}

2.8
main()
{int c1,c2;
c1=97;c2=98;
printf("%c %c",c1,c2);
}

2.9
(1)=2.5
(2)=3.5

2.10
9,11,9,10

2.12
(1)24 (2)10 (3)60 (4)0 (5)0 (6)0

第三章
3.4
main()
{int a,b,c;
long int u,n;
float x,y,z;
char c1,c2;
a=3;b=4;c=5;
x=1.2;y=2.4;z=-3.6;
u=51274;n=128765;
c1='a';c2='b';
printf("\n");
printf("a=%2d b=%2d c=%2d\n",a,b,c);
printf("x=%8.6f,y=%8.6f,z=%9.6f\n",x,y,z);
printf("x+y=%5.2f y+z=%5.2f z+x=%5.2f\n",x+y,y+z,z+x);
printf("u=%6ld n=%9ld\n",u,n);
printf("c1='%c'or %d(ASCII)\n",c1,c1);
printf("c2='%c'or %d(ASCII)\n",c2,c2);
}

3.5
57
5 7
67.856400,-789.123962
67.856400,-789.123962
67.86 -789.12,67.856400,-789.123962,67.856400,-789.123962
6.785640e+001,-7.89e+002
A,65,101,41
1234567,4553207,d687
65535,177777,ffff,-1
COMPUTER, COM

3.6
a=3 b=7/
x=8.5 y=71.82/
c1=A c2=a/

3.7
10 20Aa1.5 -3.75 +1.4,67.8/
(空3)10(空3)20Aa1.5(空1)-3.75(空1)(随意输入一个数），67.8回车

3.8
main()
{float pi,h,r,l,s,sq,sv,sz;
pi=3.1415926;
printf("input r,h\n");
scanf("%f,%f",&r,&h);
l=2*pi*r;
s=r*r*pi;
sq=4*pi*r*r;
sv=4.0/3.0*pi*r*r*r;
sz=pi*r*r*h;
printf("l=%6.2f\n",l);
printf("s=%6.2f\n",s);
printf("sq=%6.2f\n",sq);
printf("vq=%6.2f\n",sv);
printf("vz=%6.2f\n",sz);
}

3.9
main()
{float c,f;
scanf("%f",&f);
c=(5.0/9.0)*(f-32);
printf("c=%5.2f\n",c);
}

3.10
#include"stdio.h"
main()
{char c1,c2;
scanf("%c,%c",&c1,&c2);
putchar(c1);
putchar(c2);
printf("\n");
printf("%c%c\n",c1,c2);
}

第四章
4.3
(1)0 (2)1 (3)1 (4)0 (5)1

4.4
main()
{int a,b,c;
scanf("%d,%d,%d",&a,&b,&c);
if(aif(bprintf("max=%d\n",c);
else
printf("max=%d\n",b);
else if(aprintf("max=%d\n",c);
else
printf("max=%d\n",a);
}
main()
{int a,b,c,temp,max;
scanf("%d,%d,%d",&a,&b,&c);
temp=(a>b)?a:b;
max=(c>temp)?c:temp;
printf("max=%d",max);
}

4.5
main()
{int x,y;
scanf("%d",&x);
if(x<1)y=x;
else if(x<10)y=2*x-1;
else y=3*x-11;
printf("y=%d",y);
}

4.6
main()
{int score,temp,logic;
char grade;
logic=1;
while(logic)
{scanf("%d",&score);
if(score>=0&&score<=100)logic=0;
}
if(score==100)
temp=9;
else
temp=(score-score%10)/10;
switch(temp)
{case 9:grade='A';break;
case 8:grade='B';break;
case 7:grade='C';break;
case 6:grade='D';break;
case 5:
case 4:
case 3:
case 2:
case 1:
case 0:grade='E';
}
printf"score=%d,grade=%c",score,grade);
}

4.7
main()
{long int num;
int indiv,ten,hundred,thousand,ten_thousand,place;
scanf("%ld",&num);
if(num>9999) place=5;
else if(num>999) place=4;
else if(num>99) place=3;
else if(num>9) place=2;
else place=1;
printf("place=%d\n",place);
ten_thousand=num/10000;
thousand=(num-ten_thousand*10000)/1000;
hundred=(num-ten_thousand*10000-thousand*1000)/100;
ten=(num-ten_thousand*10000-thousand*1000-hundred*100)/10;
indiv=num-ten_thousand*10000-thousand*1000-hundred*100-ten*10;
switch(place)
{case 5:printf("%d,%d,%d,%d,%d\n",ten_thousand,thousand,hundred,ten,indiv);
printf("%d,%d,%d,%d,%d\n",indiv,ten,hundred,thousand,ten_thousand);
break;
case 4:printf("%d,%d,%d,%d\n",thousand,hundred,ten,indiv);
printf("%d,%d,%d,%d\n",indiv,ten,hundred,thousand);
break;
case 3:printf("%d,%d,%d\n",hundred,ten,indiv);
printf("%d,%d,%d\n",indiv,ten,hundred);
break;
case 2:printf("%d,%d\n",ten,indiv);
printf("%d,%d\n",indiv,ten);
break;
case 1:printf("%d\n",indiv);
printf("%d\n",indiv);
}
}

4.8
main()
{long i;
float bonus,bon1,bon2,bon4,bon6,bon10;
bon1=100000*0.1;
bon2=bon1+100000*0.075;
bon4=bon2+200000*0.05;
bon6=bon4+200000*0.03;
bon10=bon6+400000*0.015;
scanf("%ld",&i);
if(i<=1e5)bonus=i*0.1;
else if(i<=2e5)bonus=bon1+(i-100000)*0.075;
else if(i<=4e5)bonus=bon2+(i-200000)*0.05;
else if(i<=6e5)bonus=bon4+(i-400000)*0.03;
else if(i<=1e6)bonus=bon6+(i-600000)*0.015;
else bonus=bon10+(i-1000000)*0.01;
printf("bonus=%10.2f",bonus);
}
main()
{long i;
float bonus,bon1,bon2,bon4,bon6,bon10;
int branch;
bon1=100000*0.1;
bon2=bon1+100000*0.075;
bon4=bon2+200000*0.05;
bon6=bon4+200000*0.03;
bon10=bon6+400000*0.015;
scanf("%ld",&i);
branch=i/100000;
if(branch>10)branch=10;
switch(branch)
{case 0:bonus=i*0.1;break;
case 1:bonus=bon1+(i-100000)*0.075;break;
case 2:
case 3:bonus=bon2+(i-200000)*0.05;break;
case 4:
case 5:bonus=bon4+(i-400000)*0.03;break;
case 6:
case 7
case 8:
case 9:bonus=bon6+(i-600000)*0.015;break;
case 10:bonus=bon10+(i-1000000)*0.01;
}
printf("bonus=%10.2f",bonus);
}

4.9
main()
{int t,a,b,c,d;
scanf("%d,%d,%d,%d",&a,&b,&c,&d);
if(a>b){t=a;a=b;b=t;}
if(a>c){t=a;a=c;c=t;}
if(a>d){t=a;a=d;d=t;}
if(b>c){t=b;b=c;c=t;}
if(b>d){t=b;b=d;d=t;}
if(c>d){t=c;c=d;d=t;}
printf("%d %d %d %d\n",a,b,c,d);
}

4.10
main()
{int h=10;
float x,y,x0=2,y0=2,d1,d2,d3,d4;
scanf("%f,%f",&x,&y);
d1=(x-x0)*(x-x0)+(y-y0)*(y-y0);
d2=(x-x0)*(x-x0)+(y+y0)*(y+y0);
d3=(x+x0)*(x+x0)+(y-y0)*(y-y0);
d4=(x+x0)*(x+x0)+(y+y0)*(y+y0);
if(d1>1&&d2>1&&d3>1&&d4>1)h=0;
printf("h=%d",h);
}
第五章 循环控制
5.1
main()
{int a,b,num1,num2,temp;
scanf("%d,%d",&num1,&num2);
if(num1a=num1;b=num2;
while(b!=0)
{temp=a%b;
a=b;
b=temp;}
printf("%d\n",a);
printf("%d\n",num1*num2/a);
}

5.2
#include"stdio.h"
main()
{char c;
int letters=0,space=0,digit=0,other=0;
while((c=getchar())!='\n')
{if(c>='a'&&c<='z'||c>='A'&&c<='Z') letters++;
else if(c==' ')space++;
else if(c>='0'&&c<='9')digit++;
else other++;
}
printf("letters=%d\nspace=%d\ndigit=%d\nother=%d\n",letters,space,digit,other);
}

5.3
main()
{int a,n,count=1,sn=0,tn=0;
scanf("%d,%d",&a,&n);
while(count<=n)
{tn+=a;
sn+=tn;
a*=10;
++count;
}
printf("a+aa+aaa+...=%d\n",sn);
}

5.4
main()
{float n,s=0,t=1;
for(n=1;n<=20;n++)
{t*=n;
s+=t;
}
printf("s=%e\n",s);
}

5.5
main()
{int N1=100,N2=50,N3=10;
float k;
float s1=0,s2=0,s3=0;
for(k=1;k<=N1;k++)s1+=k;
for(k=1;k<=N2;k++)s2+=k*k;
for(k=1;k<=N3;k++)s3+=1/k;
printf("s=%8.2f\n",s1+s2+s3);
}

5.6
main()
{int i,j,k,n;
for(n=100;n<1000;n++)
{i=n/100;
j=n/10-i*10;
k=n%10;
if(i*100+j*10+k==i*i*i+j*j*j+k*k*k)
printf("n=%d\n",n);
}
}

5.7
#define M 1000
main()
{int k0,k1,k2,k3,k4,k5,k6,k7,k8,k9;
int i,j,n,s;
for(j=2;j<=M;j++)
{n=0;
s=j;
for(i=1;i{if((j%i)==0)
{n++;
s=s-i;
switch(n)
{case 1:k0=i;break;
case 2:k1=i;break;
case 3:k2=i;break;
case 4:k3=i;break;
case 5:k4=i;break;
case 6:k5=i;break;
case 7:k6=i;break;
case 8:k7=i;break;
case 9:k8=i;break;
case 10:k9=i;break;
}
}
}
if(s==0)
{printf("j=%d\n",j);
if(n>1)printf("%d,%d",k0,k1);
if(n>2)printf(",%d",k2);
if(n>3)printf(",%d",k3);
if(n>4)printf(",%d",k4);
if(n>5)printf(",%d",k5);
if(n>6)printf(",%d",k6);
if(n>7)printf(",%d",k7);
if(n>8)printf(",%d",k8);
if(n>9)printf(",%d\n",k9);
}
}
}

main()
{static int k[10];
int i,j,n,s;
for(j=2;j<=1000;j++)
{n=-1;
s=j;
for(i=1;i{if((j%i)==0)
{n++;
s=s-i;
k[n]=i;
}
}
if(s==0)
{printf("j=%d\n",j);
for(i=0;iprintf("%d,",k[i]);
printf("%d\n",k[n]);
}
}
}

5.8
main()
{int n,t,number=20;
float a=2;b=1;s=0;
for(n=1;n<=number;n++)
{s=s+a/b;
t=a,a=a+b,b=t;
}
printf("s=%9.6f\n",s);
}

5.9
main()
{float sn=100.0,hn=sn/2;
int n;
for(n=2;n<=10;n++)
{sn=sn+2*hn;
hn=hn/2;
}
printf("sn=%f\n",sn);
printf("hn=%f\n",hn);
}

5.10
main()
{int day,x1,x2;
day=9;
x2=1;
while(day>0)
{x1=(x2+1)*2;
x2=x1;
day--;
}
printf("x1=%d\n",x1);
}

5.11
#include"math.h"
main()
{float a,xn0,xn1;
scanf("%f",&a);
xn0=a/2;
xn1=(xn0+a/xn0)/2;
do
{xn0=xn1;
xn1=(xn0+a/xn0)/2;
}
while(fabs(xn0-xn1)>=1e-5);
printf("a=%5.2f\n,xn1=%8.2f\n",a,xn1);
}

5.12
#include"math.h"
main()
{float x,x0,f,f1;
x=1.5;
do
{x0=x;
f=((2*x0-4)*x0+3)*x0-6;
f1=(6*x0-8)*x0+3;
x=x0-f/f1;
}
while(fabs(x-x0)>=1e-5);
printf("x=%6.2f\n",x);
}

5.13
#include"math.h"
main()
{float x0,x1,x2,fx0,fx1,fx2;
do
{scanf("%f,%f",&x1,&x2);
fx1=x1*((2*x1-4)*x1+3)-6;
fx2=x2*((2*x2-4)*x2+3)-6;
}
while(fx1*fx2>0);
do
{x0=(x1+x2)/2;
fx0=x0*((2*x0-4)*x0+3)-6;
if((fx0*fx1)<0)
{x2=x0;
fx2=fx0;
}
else
{x1=x0;
fx1=fx0;
}
}
while(fabs(fx0)>=1e-5);
printf("x0=%6.2f\n",x0);
}

5.14
main()
{int i,j,k;
for(i=0;i<=3;i++)
{for(j=0;j<=2-i;j++)
printf(" ");
for(k=0;k<=2*i;k++)
printf("*");
printf("\n");
}
for(i=0;i<=2;i++)
{for(j=0;j<=i;j++)
printf(" ");
for(k=0;k<=4-2*i;k++)
printf("*");
printf("\n");
}
}

5.15
main()
{char i,j,k;
for(i='x';i<='z';i++)
for(j='x';j<='z';j++)
{if(i!=j)
for(k='x';k<='z';k++)
{if(i!=k&&j!=k)
{if(i!='x'&&k!='x'&&k!='z')
printf("\na--%c\tb--%c\tc--%c\n",i,j,k);
}
}
}
}
第六章 数组
6.1
#include
#define N 101
main()
{ int i,j,line,a[N];
for (i=2;ifor (i=2;ifor (j=i+1;j{if(a[i]!=0 && a[j]!=0)
if (a[j]%a[i]==0)
a[j]=0; }
printf("\n");
for (i=2,line=0;i{ if(a[i]!=0)
{ printf("%5d",a[i]);
line++; }
if(line==10)
{ printf("\n");
line=0; }
}
}

6.2
#define N 10
main()
{int i,j,min,temp,a[N];
for(i=0;iscanf("%d",&a[i]);
for(i=0;i{min=i;
for(j=i+1;jif(a[min]>a[j])min=j;
temp=a[i];
a[i]=a[min];
a[min]=temp;
}
for(i=0;iprintf("%5d",a[i]);
}

6.3
main()
{float a[3][3],sum;
int i,j;
for(i=0;i<3;i++)
for(j=0;j<3;j++)
{scanf("%f",&sum);
a[i][j]=sum;
}
for(i=0;i<3;i++)
sum=sum+a[i][i];
printf("sum=%f",sum);
}

6.4
main()
{int a[11]={1,4,6,9,13,16,19,28,40,100};
int temp1,temp2,number, end,i,j;
scanf("%d",&number);
end=a[9];
if(number>end) a[10]=number;
else
{for(i=0;i<10;i++)
{if(a[i]>number)
{temp1=a[i];
a[i]=number;
for(j=i+1;j<11;j++)
{temp2=a[j];
a[j]=temp1;
temp1=temp2;
}
break;
}
}
}
for(i=0;i<11;i++)
printf("%6d",a[i]);
}

6.5
#define N 5
main()
{int a[N]={8,6,5,4,1},i,temp;
for(i=0;i{temp=a[i];
a[i]=a[N-i-1];
a[N-i-1]=temp;
}
for(i=0;iprintf("%4d",a[i]);
}

6.6
#define N 11
main()
{int i,j,a[N][N];
for(i=1;i{a[i][i]=1;
a[i][1]=1;
}
for(i=3;ifor(j=2;ja[i][j]=a[i-1][j-1]+a[i-1][j];
for(i=1;i{for(j=1;j<=i;j++)
printf("%6d",a[i][j]);
printf("\n");
}
}

6.7
main()
{int a[16][16],i,j,k,p,m,n;
p=1;
while(p==1)
{scanf("%d",&n);
if((n!=0)&&(n<=15)&&(n%2!=0))p=0;
}
for(i=1;i<=n;i++)
for(j=1;j<=n;j++)
a[i][j]=0;
j=n/2+1;
a[1][j]=1;
for(k=2;k<=n*n;k++)
{i=i-1;
j=j+1;
if((i<1)&&(j>n))
{i=i+2;
j=j-1;
}
else
{if(i<1)i=n;
if(j>n)j=1;
}
if(a[i][j]==0)a[i][j]=k;
else
{i=i+2;
j=j-1;
a[i][j]=k;
}
}
for(i=1;i<=n;i++)
{for(j=1;j<=n;j++)
printf("%3d",a[i][j]);
printf("\n");
}
}

6.8
#define N 10
#define M 10
main()
{int i,j,k,m,n,flag1,flag2,a[N][M],max,maxi,maxj;
scanf("%d,%d",&n,&m);
for(i=0;ifor(j=0;jscanf("%d",&a[i][j]);
flag2=0;
for(i=0;i{max=a[i][0];
for(j=0;jif(max{max=a[i][j];
maxj=j;
}
for(k=0,flag1=1;kif(max>a[k][maxj])flag1=0;
if(flag1)
{ printf("\na[%d][%d]=%d\n",i,maxj,max);
flag2=1;
}
}
if(!flag2) printf("NOT");
}

6.9
#include
#define N 15
main()
{int i,j,number,top,bott,min,loca,a[N],flag;
char c;
for(i=0;i<=N;i++)
scanf("%d",&a[i]);
flag=1;
while(flag)
{scanf("%d",&number);
loca=0;
top=0;
bott=N-1;
if((numbera[N-1]))
loca=-1;
while((loca==0)&&(top<=bott))
{min=(bott+top)/2;
if(number==a[min])
{loca=min;
printf("number=%d,loca=%d\n",number,loca+1);
}
else if(numberbott=min-1;
else
top=min+1;
}
if(loca==0||loca==-1)
printf("%d not in table\n",number);
printf("continue Y/N or y/n\n");
c=getchar();
if(c=='N'||c=='n')flag=0;
}
}

6.10
main()
{int i,j,uppn,lown,dign,span,othn;
char text[3][80];
uppn=lown=dign=span=othn=0;
for(i=0;i<3;i++)
{gets(text[i]);
for(j=0;j<80&&text[i][j]!='\0';j++)
{if(text[i][j]>='A'&&text[i][j]<='Z')
uppn++;
else if(text[i][j]>='a'&&text[i][j]<='z')
lown++;
else if(text[i][j]>='0'&&text[i][j]<='9')
dign++;
else if(text[i][j]==' ')
span++;
else
othn++;
}
}
for(i=0;i<3;i++)
printf("%s\n",text[i]);
printf("uppn=%d\n",uppn);
printf("lown=%d\n",lown);
printf("dign=%d\n",dign);
printf("span=%d\n",span);
printf("othn=%d\n",othn);
}

6.11
main()
{static char a[5]={'*','*','*','*','*'};
int i,j,k;
char space=' ';
for(i=0;i<=5;i++)
{printf("\n");
for(j=1;j<=3*i;j++)
printf("%1c",space);
for(k=0;k<=5;k++)
printf("%3c",a[k]);
}
}

6.12
#include
main()
{int i,n;
char ch[80],tran[80];
gets(ch);
i=0;
while(ch[i]!='\0')
{if((ch[i]>='A')&&(ch[i]<='Z'))
tran[i]=26+64-ch[i]+1+64;
else if((ch[i]>='a')&&(ch[i]<='z'))
tran[i]=26+96-ch[i]+1+96;
else
tran[i]=ch[i];
i++;
}
n=i;
for(i=0;iputchar(tran[i]);
}

6.13
main()
{char s1[80],s2[40];
int i=0,j=0;
scanf("%s",s1);
scanf("%s",s2);
while(s1[i]!='\0')i++;
while(s2[j]!='\0')s1[i++]=s2[j++];
s1[i]='\0';
printf("s=%s\n",s1);
}

6.14
#include
main()
{int i,resu;
char s1[100],s2[100];
gets(s1);
gets(s2);
i=0;
while((s1[i]==s2[i])&&(s1[i]!='\0'))i++;
if(s1[i]=='\0'&&s2[i]=='\0')resu=0;
else
resu=s1[i]-s2[i];
printf("s1=%s,s2=%s,resu=%d\n",s1,s2,resu);
}

6.15
#include"stdio.h"
main()
{char from[80],to[80];;
int i;
scanf("%s",from);
for(i=0;i<=strlen(from);i++)
to[i]=from[i];
printf("%s\n",to);
}

第七章
7.1
hcf(u,v)
int u,v;
{int a,b,t,r;
if(u>v){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=%d\n",h);
l=lcd(u,v,h);
printf("L.C.D=%d\n",l);
}

7.2
#include"math.h"
float x1,x2,disc,p,q;
greater_than_zero(a,b)
float 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)<=1e-5)
{equal_to_zero(a,b);
printf("x1=%5.2f\tx2=%5.2f\n",x1,x2);
}
else if(disc>0)
{greater_than_zero(a,b);
printf("x1=%5.2f\tx2=%5.2f\n",x1,x2);
}
else
{smaller_than_zero(a,b);
printf("x1=%5.2f+%5.2fi\tx2=%5.2f-%5.2fi\n",p,q,p,q);
}
}

7.3
main()
{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;nif(number%n==0)
flag=0;
return(flag);
}

7.4
#define N 3
int array[N][N];
convert(array)
int array[3][3];
{int i,j,t;
for(i=0;ifor(j=i+1;j{t=array[i][j];
array[i][j]=array[j][i];
array[j][i]=t;
}
}
main()
{int i,j;
for(i=0;ifor(j=0;jscanf("%d",&array[i][j]);
convert(array);
for(i=0;i{printf("\n");
for(j=0;jprintf("%5d",array[i][j]);
}
}

7.5
main()
{char str[100];
scanf("%s",str);
inverse(str);
printf("%s\n",str);
}
inverse(str)
char str[];
{char t;
int i,j;
for(i=0,j=strlen(str);i{t=str[i];
str[i]=str[j-1];
str[j-1]=t;
}
}

7.6
char concate(str1,str2,str)
char str1[],str2[],str[];
{int i,j;
for(i=0;str1[i]!='\0';i++)
str[i]=str1[i];
for(j=0;str2[j]!='\0';j++)
str[i+j]=str2[j];
str[i+j]='\0';
}
main()
{char s1[100],s2[100],s[100];
scanf("%s",s1);
scanf("%s",s2);
concate(s1,s2,s);
printf("\ns=%s",s);
}

7.7
main()
{char str[80],c[80];
void cpy();
gets(str);
cpy(str,c);
printf("\n%s\n",c);
}
void cpy(s,c)
char s[],c[];
{int i,j;
for(i=0,j=0;s[i]!='\0';i++)
if(s[i]=='a'||s[i]=='A'||s[i]=='e'||s[i]=='E'||s[i]=='i'||
s[i]=='I'||s[i]=='o'||s[i]=='O'||s[i]=='u'||s[i]=='U')
{c[j]=s[i];j++;}
c[j]='\0';
}

7.8
main()
{char str[80];
scanf("%s",str);
insert(str);
}
insert(str)
char str[];
{int i;
for(i=strlen(str);i>0;i--)
{str[i*2]=str[i];
str[i*2-1]=' ';
}
printf("%s\n",str);
}

7.9
int alph,digit,space,others;
main()
{char text[80];
gets(text);
alph=0,digit=0,space=0,others=0;
count(text);
printf("\nalph=%d,digit=%d,space=%d,others=%d\n",alph,digit,space,others);
}
count(str)
char str[];
{int i;
for(i=0;str[i]!='\0';i++)
if((str[i]>='a'&&str[i]<='z')||(str[i]>='A'&&str[i]<='Z'))
alph++;
else if(str[i]>='0'&&str[i]<='9')
digit++;
else if(strcmp(str[i],' ')==0)
space++;
else
others++;
}

7.10
int alph(c)
char c;
{if((c>='a'&&c<='z')||(c>='A'&&c<='Z'))
return(1);
else
return(0);
}
int longest(string)
char string[];
{int len=0,i,length=0,flag=1,place,point;
for(i=0;i<=strlen(string);i++)
if(alph(string[i]))
if(flag)
{point=i;
flag=0;
}
else
len++;
else
{flag=1;
if(len>length)
{length=len;
place=point;
len=0;
}
}
return(place);
}
main()
{int i;
char line[100];
gets(line);
for(i=longest(line);alph(line[i]);i++)
printf("%c",line[i]);
printf("\n");
}

7.11
#define N 10
char str[N];
main()
{int i,flag;
for(flag=1;flag==1;)
{scanf("%s",str)

我已经传给你了，与君共勉，好好学习这书

C++程序设计题解与上机指导
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我有word版的。。。可能你不用了～～～