P131_3#include<iostream.h>#include<math.h>structpoint{floatx,y,z;};floatdistance(pointp1,pointp2){floatd;d=sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y)+(p1.z-p2.z)*(p1.z-p2.z));returnd;}voidmain(){pointp1,p2;floatlen;cout<<"请输入第一个点的三维坐标x,y,z\n";cin>>p1.x>>p1.y>>p1.z;cout<<"请输入第二个点的三维坐标x,y,z\n";cin>>p2.x>>p2.y>>p2.z;len=distance(p1,p2);cout<<"两点的距离为："<<len<<endl;}P131_4voidmain(){studs[50];intn;cout<<"请输入全班学生人数\n";cin>>n;input(s,n);average(s,n);sort(s,n);cout<<"按C语言从高到低排序后的结果\n";print(s,n);}P131_4#include<iostream.h>structstud{charid[10];charname[10];charsex;floatcpp;};voidinput(studs[],intn){cout<<"输入"<<n<<"个学生的学号、姓名、性别和C语言成绩\n";for(inti=0;i<n;i++)cin>>s[i].id>>s[i].name>>s[i].sex>>s[i].cpp;}voidaverage(studs[],intn){intm=0,w=0;floatave1=0,ave2=0;for(inti=0;i<n;i++){if(s[i].sex=='M'||s[i].sex=='m'){ave1=ave1+s[i].cpp;m++;}else{ave2=ave2+s[i].cpp;w++;}}ave1=ave1/m;ave2=ave2/w;cout<<"男生的人数为:"<<m<<endl<<"平均成绩为:"<<ave1<<endl;cout<<"女生的人数为:"<<w<<endl<<"平均成绩为:"<<ave2<<endl;}voidsort(studs[],intn){studt;for(inti=0;i<n-1;i++)for(intj=i+1;j<n;j++)if(s[i].cpp<s[j].cpp)t=s[i],s[i]=s[j],s[j]=t;}voidprint(studs[],intn){cout<<"学号\t姓名\t性别\tC语言成绩\n";for(inti=0;i<n;i++)cout<<s[i].id<<'\t'<<s[i].name<<'\t'<<s[i].sex<<'\t'<<s[i].cpp<<endl;}P131_1#include<iostream.h>structtime{inthour,minute,second;};voidmain(void){timet1;cout<<"请输入时间(小时分秒):\n";cin>>t1.hour>>t1.minute>>t1.second;cout<<"输入的时间为:\n";cout<<t1.hour<<":"<<t1.minute<<":"<<t1.second<<endl;}P131_5#include<iostream.h>#include<stdlib.h>enumseason{Spring,Summer,Autumn,Winter};voidmain(){seasons;inti;cout<<"输入一个0-3之间的整数\n";cin>>i;if(i>=6||i<0){cout<<"输入不正确\n";exit(0);}s=(season)i;switch(s){caseSpring:cout<<"春季\n";break;caseSummer:cout<<"夏季\n";break;caseAutumn:cout<