C语言程序设计第二版第四章第七章课后答案

1、输入函数scanf的参数错误，应该为：scanf(%f,&k);2、|12341234|3、ff104、1,3,15、原字符串左边加空格再加字符串本省，字符个数总和为5个6、scanf(%d,%d,%c,%c,&a1,&a2,&c1,&c2);7、printf(a+b=%d\n,a+b);printf(a-b=%d\n,a-b);printf(a*b=%d\n,a*b);printf(a/b=%d\n,a/b);printf((float)a/b=%f\n,(float)a/b);printf(a%b=%d\n,a%b);8、voidmain(){floatr;floats,c;printf(pleaseinputthenumber:);scanf(%f,&r);if(r=0){s=3.14*r*r;c=2*3.14*r;printf(s=%f,c=%f\n,s,c);}elseprintf(youinputnumberiserror!);}9voidmain(){intn;printf(pleaseinputthenumber:);scanf(%d,&n);if(n=100&&n=999)printf(%d%d%d,n%10,(n/10)%10,n/100);elseprintf(youinputnumberiserror!);}10、voidmain(){inti,j,k;scanf(%d,%d,%d,&i,&j,&k);((i%2!=0?1:0)+(j%2!=0?1:0)+(k%2!=0?1:0))==2?printf(YES\n):printf(NO\n);}11、voidmain(){chara;scanf(%c,&a);printf(%c,%c,%c,a-1,a,a+1);printf(%d,%d,%d,a-1,a,a+1);}12、voidmain(){floata,b,c,s,Area;scanf(%f,%f,%f,&a,&b,&c);if(a+bc||a+cb||b+ca){s=(a+b+c)/2;Area=sqrt(s*(s-a)*(s-b)*(s-c));printf(%f\n,Area);}elseprintf(youinputthenumberiserror!\n);}习题41：02：203：(x30&&x20)||(x-100)4:***a=25,b=14,c=16***5:376:if(a=b)printf(1);elseprintf(2);7、#includestdio.hvoidmain(){chara,b,t1,t2;scanf(%c,%c,&a,&b);t1=ab?a:b;t2=ab?a:b;if((t1-t2)%2==0)printf(%c,%c,a+1,b+1);elseprintf(%c,%c,a-1,b-1);getch();}8、#includestdio.hvoidmain(){inttemp1=0,temp2=0,x,y,i=1;printf(Pleaseinput(x,y):);scanf(%d,%d,&x,&y);while((i*y)=x){if(x==(i*y)){temp1=1;break;}temp2=i;i++;}if(temp1)printf(%d/%d=%d,x,y,i);elseprintf(%d/%d---shang=%d,yushu=%d,x,y,temp2,x-y*temp2);getch();}9、#includestdio.hvoidmain(){floatx,y,m=0,n=0;scanf(%f,%f,&x,&y);n=(x-2)*(x-2);m=(y-2)*(y-2);if((m+n)=1)printf((%.3f,%.3f)Intheyuan,x,y);elseprintf((%.3f,%.3f)outoftheyuan,x,y);getch();}10、#includestdio.hvoidmain(){inttemp=0,month,year;printf(Pleaseinput(year,month):);scanf(%d,%d,&year,&month);if((year%400==0)||(year%4==0&&year%100!=0))temp=1;if(month==2){if(temp)printf(%dyear%dmonthhave29,year,month);elseprintf(%dyear%dmonthhave28,year,month);}elseif(month%2==0)printf(%dyear%dmonthhave30,year,month);elseprintf(%dyear%dmonthhave31,year,month);getch();}11、switch(a/10){case5:m=4;break;case4:m=3;break;case3:m=2;break;case2:m=1;break;default:m=5;}12、方法一：#includestdio.hvoidmain(){intx,y;scanf(%d,&x);if(x0&&x-5)y=x-1;elseif(x==0)y=x;elseif(x0&&x8)y=x+1;printf(%d,y);getch();}方法二：#includestdio.hvoidmain(){intx,y;scanf(%d,&x);if(x8&&x-5)if(x==0)y=x;{floatx,y,t;printf(Entertwonumber(x,y):);scanf(%f,%f,&x,&y);SWAP(x,y);printf(\n\nExchanged:x=%f,y=%f,x,y);getch();}5、#includestdio.hintfib(intn){intp;if(n==0)p=0;elseif(n==1)p=1;elsep=fib(n-1)+fib(n-2);returnp;}voidmain(){intn;printf(Pleaseinputfib:);scanf(%d,&n);printf(\n\nfibonacci=%d,fib(n));}6、#includestdio.hlongfac(intn){longf;if(n==0)f=1;elsef=n*fac(n-1);returnf;}voidmain(){intm,n;longf;printf(Pleaseinput(m,n):);scanf(%ld,%ld,&m,&n);f=fac(n+m)+fac(n);printf(\n\nfibonacci=%ld,f);}7、#includestdio.hvoidlist(){inti,j;for(i=1;i=9;i++){for(j=1;j=i;j++)printf(%d*%d=%d,i,j,i*j);printf(\n);}}voidmain(){list();}8、#includestdio.hinthe(intn){inti,s=0;for(i=1;in;i++)if(n%i==0)s+=i;returns;}voidmain(){inti,j;for(i=1;i30000;i++){for(j=1;j30000;j++)if((he(i)==j)&&(he(j)==i)&&(i!=j))printf(%d---%d,i,j);}}9、#includestdio.h#definemax100structwork{longsid;charname[15];}worker[max];intsize=0;structwork*set_list(){do{printf(\n\nPleaseinput(sid,name):);scanf(%ld,%s,&worker[size].sid,worker[size].name);size++;}while(worker[size-1].sid!=0);returnworker;}voidpaixu(structworka[]){inti,j,k;longt;charv[15];for(i=0;isize-1-2;i++){k=i;for(j=i;jsize-2;j++)if(a[i].sida[j].sid)k=j;if(k!=i){t=a[i].sid;a[i].sid=a[j].sid;a[j].sid=t;strcpy(v,a[i].name);strcpy(a[i].name,a[j].name);strcpy(a[j].name,v);}}for(i=0;i=size-2;i++)printf(sid:%ld\tname:%s\n\n,a[i].sid,a[i].name);getch();}voidselect(structworka[]){inti=0,found=1;longnum;printf(Inputselectsid:);scanf(%ld,&num);for(i=0;i=size-2;i++){if(a[i].sid==num){found=0;printf(%ld:%s,num,a[i].name);break;}}if(found)printf(\n\nNOthissid!!!);getch();}voidmain(){structwork*p;p=set_list();paixu(p);select(p);}10、#includestdio.hfloatjiecheng(intn){longs=1;inti;for(i=1;i=n;i++)s=s*i;returns;}floatchengfang(floatx,intn){floats=1;inti;for(i=1;i=n;i++)s=s*x;returns;}floatf(floatx,intn){floats=1,t=0;inti=1,j=-1;for(i=1;i=n;i++){t=j*chengfang(x,2*i)/jiecheng(2*i);s+=t;j=j*j;}returns;}main(){floats1=0,s2=0,s3=0,s4=0,x=5.6;intn=7;s1=f(x,n);s2=f(x+2.3,n);s3=f(x-3.2,n+3);s4=s1/(s2+s3);printf(%f,s4);getch();}习题71：（1）D（2）A（3）D（4）B（5）D2：（1）1544678234（2）63333:（1）a[8]=data;k=0a[k]=tempbreakk=8(2)%sstr[i]='Z'c[str[i]+26-'a']++i+'a'4、/*题目：求一组成绩的平均分数以及高于平均分的成绩。*/#includestdio.h#definemax100voidmain(){floata[max],s=0,average=0;inti,n;printf(PleaseinputN:);/*输入要处理元素的个数*/scanf(%d,&n);printf(\nPleaseinput%dgeshu:,n);/*输入90，85，92，77，80，62*/for(i=0;in;i++){scanf(%f,&a[i]);s+=a[i];}average=s/n;printf(\naverage=%.2f\n,average);/*输出81.00*/for(i=0;in;i++)if(a[i]average)printf(%.2f,a[i]);/*输出90.00，85.00，92.00*/}5、/*题目：编写程序，输入一组整数，将他们排序后由小到大输出。*/#includestdio.h#definemax100voidmain(){inta[max