第四章課后編程題答案

1、第四章課后編程題答案/編寫一個函數(shù)，計算直角坐標系中點a(xO,yO)到點b(xl,y1)的距離。#includc <i()strcam.h>#includc <math.h>float lcngth(float xO,float yO,float xl,float yl) 求兩點距離的于函數(shù)return sqrt(xO-xl)*(xO-x 1 )+(yO-y 11);void main。float xO.xhyO,yl;cout<<MInput x and y of a point:"cin>>xO>>yO;cout

2、71;HInput x and y of b point:11;cin»xl»yl;cout<<MTlic length from a to b is H<<length(xO,)0,x 1 ,y 1)«end 1;/求a汁b!+c!的值，其中求n!要用一個函數(shù)實現(xiàn)，通過主函數(shù)輸入a、b和c的值，并在主函 數(shù)中輸出計算的結(jié)果。#includc <i()strcam.h>int factorial(int n)/求兩點距離的于函數(shù)int sum=l;f()r (int i=l;i<=n；i+)sumw=i;return su

3、m;void mainQint a,b,c;cout«MInput a,b,c:M;cin>>a>>b>>c;cout<<Ha 葉 b!+c!="V <fiict()rial(ji)+fiicmrkd(b)+fiictoriid(c)<<ciKll;/編寫一個函數(shù)。該函數(shù)讀入一個整數(shù)，并判斷這個整數(shù)是否為一個回文數(shù)宇。例如4, 44, 434, 4334, 43534都是回文數(shù)宇。#includc <i()strcam.h>bool palindromc(int n)/判斷n是否為回文的于國數(shù)in

4、t a20;int m=n；int i=0;int temp,num;while (m>0)/將教字的各位反向放直在數(shù)組a中ai=m%10;m=m/10;i+；tcmp=i/2;/雷要比較的次數(shù)num=-i;/數(shù)宇的是高位存儲在anum中f()r (int j=O;j<tcmp;j+)if (aj!=anum-jj) return false;/如果出現(xiàn)不相等的情況立即退出return mu；/若比較的各個位直都相等，則為回文void mainQint number;c()ut<<HInput the number11;cin>>numbcr;if (pal

5、indromc(numbcr)cout<<numbcr<<H is a palindr()me.H<<cndl;elsec()ut<<number<<M is not a palindromc.M<<cndl;/編寫一個程序，為選修3、4和5門課程的學生計算平均分，其中求平均分要用重載函數(shù) 實現(xiàn)#include <i()strcam.h>float avcrage(float a,float b,float c)/求三門課程平均分于函數(shù)return (a+b+c)/3;float average(float a

6、,float b,float c,float d) 求四門課程平均分于函數(shù)return (a+b+c+d)/4;float average (float a,float b,float c»float d,float e)/求五門課程平均分于函數(shù)return (a+b+c+d+c)/5;void mainQint number;float sl2,s3,s4,s5;cout«,The total of student's courses is H;cin>>numbcr;if (numbcr=3)c()ut«Mlnput three score

7、 of student?1; cin>>sl>>s2>>s3;cout<<nThc average is °<<average(s 1 ,s2,s3)<<cndl;else if (numbcr=4)cout<<Mlnput four score of student?'cin>>sl>>s2>>s3>>s4;cout<<nThc average is °<<avcrage(s 1 ,s2,s3,s4)<&

8、lt;cndl;c()ut<<nlnput three score of studcnt:H;cin>>sl>>s2>>s3>>s4>>s5;cout«HThc average is M<<avcragr(sl,s2,s3,s4,s5)«cndl;/用遞歸方法將一個整數(shù)n轉(zhuǎn)換成宇符串。#includc <i()strcam>#includc <string>using namespace std;string c<)nvcrt(int n);string num

9、string(nH);void mainQint number;cout<<1,Input the number: M;cin>>numbcr;c()ut<< Hc(>nvcrted string is ”；cout<<convcrt(numbcr) < < end 1;string convert(int n)/遞歸函數(shù)if (n/l()=O)&&(n=0)rcuini ',H;elsenumsmng=convcr<n/10).appcnd(string(l ,(n%l 0+48);/將各位數(shù)轉(zhuǎn)換

10、為宇符后創(chuàng)建 宇符串，加到最后return num string;/編寫一個函數(shù)。該函數(shù)讀入一個整數(shù)，然后將這個整數(shù)上每個位的數(shù)字按照相反的順序輸 出。/例如輸入的整數(shù)為12345,輸出結(jié)果為54321。#includc <i()strcam.h>void rcvcrsc(intn)/反向顯示整數(shù) ninta20;/儲n的各位，屋多20位int m=n；int i=0;while (m>0)/提取n的各位ai=m%10;m=m/10;i+；c()ut<< Hrccrscd number is M;for (int j=O;j<=i-l;j+)/反向輸出各位c

11、out<<aj;cout<<cndl;void mainOint number;cout<<HInput the number: M;cin>>numbcr;re-crsc(numbcr);輸入三個教字，數(shù)字可以為整形或浮點型，分別編寫函數(shù)來求解三個數(shù)宇的最大值、黒小 值和平均值，要求在主函數(shù)中完成數(shù)宇的輸入和計算結(jié)果的輸出。#includc <i（）strcam.h> #include <iom:inip.h> float fmaxfminfavcragc； int max,min,avcragc;浮點型處理函敵/整型處

12、湼函數(shù)void calculatc(float fa,float fb,float fc) fmax= fa>=fb?fa: fb; fmax=fmax>=fc?fmax:fc; fmin= fa<=fb?fa: fb; frnin=ftnin<=fc?frnin:fc; favcragc=(fa+fb+fc)/3;void calculatc(int a,int c) max=a>=b?a:b;max=max>=c?max：c;min=a<=b?a:b;min=min<=c?min:c; avcragc=(a+b+c)/3;void

13、 mainOint 8123;float fl ,f2,f3;int type；cout<<nInput the type： float(l) or int(0):H;cin>>t)pc；while (t)pc!=0)&&(lypc!= 1)/輸入類型錯誤時再次輸入cout<<MPlease input 1 or 0:M;cin>>tpc;cout<<HInput three numbcrs：H;if(t>pe=l)浮點型數(shù)據(jù)cin»fl»f2»f3;calculatc(fl,£2,； c()ut<<sctw(8)<<,maxn<<sciw(8)<<nmin°<<sct?,(12)<<HavcrarH<<cndl; c()ut<<sc(8)<<fmax<<sctw(8)<<fmin<<sctw(12)<<favcrage<<cndl;else整型數(shù)據(jù)cin>>sl>>s2>>s3;calculates hs2,s3); c()ut