为什么如下程序不能显示所有员工信息，不能按职务查找，但能按性别查找？

Question

#include<stdio.h>
#include<string.h>
struct employee
{int num; //编号  
char name[20]; //姓名
char sex[20]; //性别
int age; //年龄
char job[20]; //职务
char dep[50]; //部门
}employee[50];
void addemp()
{char c[2];
do
{
int n=0;
printf("姓名\n");
scanf("%s",&employee[n].name);
printf("性别\n");
scanf("%s",&employee[n].sex);
printf("编号\n");
scanf("%d",&employee[n].num);
printf("年龄\n");
scanf("%d",&employee[n].age);
printf("职务\n");
scanf("%s",&employee[n].job);
printf("部门\n");
scanf("%s",&employee[n].dep);
n++;
printf("添加下一员工信息，请按y\n");
scanf("%s",&c);
}
while(!(strcmp(c,"y")));
}
void showemp()
{int i;
printf(" 编号 姓名 性别 年龄 职务 部门 \n");
for(i=1;employee[i].num!=0;i++);
{
printf("%d",employee[i].num);
printf("%s %s ",employee[i].name,employee[i].sex);
printf("%d ",employee[i].age);
printf("%s %s",employee[i].job,employee[i].dep);
}
}

void search_sex()
{char a[20];
int i;
printf("输入性别\n");
scanf("%s",&a);
for(i=0;i<50;i++)  
{if(strcmp(a,employee[i].sex)==0)
printf(" 编号 姓名 性别 年龄 职务 部门 \n %d %s %s %d %s %s",employee[i].num,employee[i].name,employee[i].sex,employee[i].age,employee[i].job,employee[i].dep);
}  
}
void search_dep()
{char b[20];
int i;
printf("输入职务\n");
scanf("%s",&b);
for(i=0;i<50;i++)  
{if(strcmp(b,employee[i].dep)==0)
printf(" 编号 姓名 性别 年龄 职务 部门 \n%d %s %s %d %s %s",employee[i].num,employee[i].name,employee[i].sex,employee[i].age,employee[i].job,employee[i].dep);
}
}
void main()
{int i;
for (i=0;i<50;i++)
printf("*");
printf("\n 员工信息管理系统\n");
printf (" 通信二班--刘尧\n");

printf("@ 0 退出员工信息管理系统。 @\n");
printf("@ 1 输入员工信息 @\n");
printf("@ 2 显示所有员工信息 @\n");
printf("@ 3 查找某部门员工信息 @\n");
printf("@ 4 查找男女员工信息 @\n");
for(i=0;i<50;i++)
printf("*");
printf("\n");
//菜单页面
int n;
scanf("%d",&n);
for(i=1;i!=0;i++)
{switch(n)
{ case 1:addemp();printf("\n");break;
case 2:showemp();printf("\n");break;
case 3:search_dep();printf("\n");break;
case 4:search_sex();printf("\n");break;
default:printf("输入有误，请重新输入\n");
}
printf("请输入下一项操作代码，否则按0退出\n");
scanf("%d",&n);
}
}

Answer 1

1、void showemp()函数中for(i=1;employee[i].num!=0;i++);循环应该从i=0开始啊~~不知道你不能显示出来的员工信息有多少，如果是这个原因，只会少显示1个。2、void search_dep() 开起来没问题，只是你申请的b[20]和前面结构体中申明的dep[50]不一样，改过来看看能不查找~~~

Answer 2

#ifndef __OPTIMIZATION_H__#define __OPTIMIZATION_H__//////////////////////////////////////////////////////////////////////////// class TOptimization//// $ 求函数一个或多个参数的最小值//// 该类默认对一个参数优化，一般只要输入优化参数数目// 优化目标函数就可以使用。//// ...主要代码来自：// Numerical Recipes in C++// The Art of Scientific Computing// Second Edition// William H. Press Saul A. Teukolsky// William T. Vetterling Brian P. Flannery//// 中译本：// C++ 数值算法(第二版) 胡健伟 赵志勇 薛运华 等译// 电子工业出版社 北京 (2005)//// Author: Jian Feng// Email: [e-mail]// Dec. 9, 2006//////////////////////////////////////////////////////////////////////////////&nbsp;// 输入函数：//// @MaxIterationStep: 最大迭代次数， 默认 1000// @ParameterNumbers: 优化参数数目， 默认 1// @InitMatrix: 初始化矩阵参数(N*N)， 默认// @Tolerance: 容许公差， 默认 1E-7//// 执行函数：//// @ExecutePowell: 利用powell方法进行多参数优化// @ExecuteBrent: 利用brent方法进行单参数优化//// 输出函数：//// @OptimizatedParameters: 优化结果数据// @ObjectiveFunctionValue: 目标函数在优化值处的值//// 使用示例：//// 1. 单参数// double objfun(double a){// double sum = 0;// for(int i = 0; i < DataPoints; ++i)// sum += SQR(Exps[i] - Theo(a));// }// double value// TOptimization opt;// if(opt.ExecuteBrent(objfun, -10, -1)) opt.OptimizatedParameters(&value);//// 2. 多参数// double objfun(double *a){// double sum = 0;// for(int i = 0; i < DataPoints; ++i)// sum += SQR(Exps[i] - Theo(a));// }// double value[3]// TOptimization opt(3);// double ival[3] = ;// if(opt.ExecutePowell(objfun, ival)) opt.OptimizatedParameters(value);//namespace{static int ncom; //公用变量static double *pcom_p; //公用变量static double *xicom_p; //公用变量static double (*nrfunc)(double*); //公用函数指针}class TOptimization{private:typedef double (*Reff)(double *);typedef double (*Ptrf)(double );public:TOptimization(int n = 1);~TOptimization()//主要方法void ParameterNumbers(int n)//利用powell方法对一个或多个参数优化bool ExecutePowell(Reff obj, double *a = 0);//利用brent方法对一个参数优化，需给出参数所在的区间bool ExecuteBrent(Ptrf obj, double vFrom = 0, double vTo = 1);void OptimizatedParameters(double *a)void OptimizatedParameters(double &a)//void OptimizatedParameters(double *a){&nbsp;&nbsp;// if(method) for(int i=0; i<num; ++i) a[i]=coef[i];// else *a = vmin;//}//其它方法void InitMatrix(double **m){for(int i=0; i<num; ++i)for(int j = 0; j<num; ++j)matx[i][j]=m[i][j];&nbsp;setm = true;}void MaxIterationStep(int s)void Tolerance(double eps)double ObjectiveFunctionValue()constprivate:double brent(double ax, double bx, double cx, Ptrf f, double tol, double &xmin, int &flag);void mnbrak(double &ax, double &bx, double &cx, double &fa, double &fb, double &fc, Ptrf func);void linmin(double *p, double *xi, double &fret, Reff func);bool powell(double *p, double **xi, double ftol, int &iter, double &fret, Reff func);void shft2(double &a, double &b, const double c)void shft3(double &a, double &b, double &c, const double d)double SQR(double x)void SWAP(double &a, double &b)double SIGN(const double &a, const double &b)double MAX(const double &a, const double &b)void AllocateMemory();void FreeMemory();static double f1dim(double x){int j;double *xt = new double [ncom];//Vec_Dp &pcom=*pcom_p,&xicom=*xicom_p;double *pcom = pcom_p, *xicom = xicom_p;&nbsp;for (j=0;j<ncom;j++)xt[j]=pcom[j]+x*xicom[j];//delete []xt;double val = nrfunc(xt);delete []xt;return val;}bool setm; //是否设置优化方向初始矩阵&nbsp;int num; //优化参数int ITMAX; //最大迭代数int iter; //实际迭代步数int method; //优化方法 0: 1-D brent, 2: M-D Powell&nbsp;double vmin; //一维优化参数double ftol; //容许差double fret; //目标函数值double *coef; //多维优化参数值double **matx; //多维优化参数方向的初始值};//////////////////////////////////////////////////////////////////////////inline TOptimization::TOptimization(int n ){num = n;ftol = 1e-7;ITMAX = 1000;iter = 0;fret = 0.;vmin = 0.;method = 0;setm = false;AllocateMemory();}inline void TOptimization::AllocateMemory(){pcom_p = new double [num];xicom_p = new double [num];coef = new double [num];matx = new double *[num];for(int i = 0; i < num; ++i){coef[i] = 0.;matx[i] = new double [num];for(int j = 0; j < num; ++j)matx[i][j]=(i == j ? 1.0 : 0.0);&nbsp;}}inline void TOptimization::FreeMemory(){for(int i = 0; i < num; ++i){delete []matx[i];}delete []matx;delete []pcom_p;delete []xicom_p;delete []coef;}inline bool TOptimization::ExecutePowell(Reff obj, double *a){method = 1;if(a)for(int i = 0; i < num; ++i) coef[i] = a[i];return powell(coef, matx, ftol, iter, fret, obj);}inline bool TOptimization::ExecuteBrent(Ptrf obj, double vFrom, double vTo){method = 0;int flag;double cx, fa, fb, fc;mnbrak(vFrom,vTo,cx,fa,fb,fc,obj);fret = brent(vFrom,vTo,cx,obj, ftol,vmin, flag);return flag ? true : false;}inline void TOptimization::mnbrak(double &ax, double &bx, double &cx, double &fa,&nbsp;double &fb, double &fc, Ptrf func){const double GOLD=1.618034,GLIMIT=100.0,TINY=1.0e-20;double ulim,u,r,q,fu;fa=func(ax);fb=func(bx);if (fb > fa) {SWAP(ax,bx);SWAP(fb,fa);}cx=bx+GOLD*(bx-ax);fc=func(cx);while (fb > fc) {r=(bx-ax)*(fb-fc);q=(bx-cx)*(fb-fa);u=bx-((bx-cx)*q-(bx-ax)*r)/(2.0*SIGN(MAX(fabs(q-r),TINY),q-r));ulim=bx+GLIMIT*(cx-bx);if ((bx-u)*(u-cx) > 0.0) {fu=func(u);if (fu < fc) {ax=bx;bx=u;fa=fb;fb=fu;return;} else if (fu > fb) {cx=u;fc=fu;return;}u=cx+GOLD*(cx-bx);fu=func(u);} else if ((cx-u)*(u-ulim) > 0.0) {fu=func(u);if (fu < fc) {shft3(bx,cx,u,cx+GOLD*(cx-bx));shft3(fb,fc,fu,func(u));}} else if ((u-ulim)*(ulim-cx) >= 0.0) {u=ulim;fu=func(u);} else {u=cx+GOLD*(cx-bx);fu=func(u);}shft3(ax,bx,cx,u);shft3(fa,fb,fc,fu);}}&nbsp;inline double TOptimization::brent(double ax, double bx, double cx,&nbsp;Ptrf f, double tol, double &xmin, int &flag){flag = 1;const double CGOLD=0.3819660;const double ZEPS=1.0e-20;int iter;double a,b,d=0.0,etemp,fu,fv,fw,fx;double p,q,r,tol1,tol2,u,v,w,x,xm;double e=0.0;a=(ax < cx ? ax : cx);b=(ax > cx ? ax : cx);x=w=v=bx;fw=fv=fx=f(x);for (iter=0;iter<ITMAX;iter++) {xm=0.5*(a+b);tol2=2.0*(tol1=tol*fabs(x)+ZEPS);if (fabs(x-xm) <= (tol2-0.5*(b-a))) {xmin=x;return fx;}if (fabs(e) > tol1) {r=(x-w)*(fx-fv);q=(x-v)*(fx-fw);p=(x-v)*q-(x-w)*r;q=2.0*(q-r);if (q > 0.0) p = -p;q=fabs(q);etemp=e;e=d;if (fabs(p) >= fabs(0.5*q*etemp) || p <= q*(a-x) || p >= q*(b-x))d=CGOLD*(e=(x >= xm ? a-x : b-x));else {d=p/q;u=x+d;if (u-a < tol2 || b-u < tol2)d=SIGN(tol1,xm-x);}} else {d=CGOLD*(e=(x >= xm ? a-x : b-x));}u=(fabs(d) >= tol1 ? x+d : x+SIGN(tol1,d));fu=f(u);if (fu <= fx) {if (u >= x) a=x; else b=x;shft3(v,w,x,u);shft3(fv,fw,fx,fu);} else {if (u < x) a=u; else b=u;if (fu <= fw || w == x) {v=w;w=u;fv=fw;fw=fu;} else if (fu <= fv || v == x || v == w) {v=u;fv=fu;}}}flag = 0;xmin=x;return fx;}inline void TOptimization::linmin(double *p, double *xi, double &fret, Reff func){int j, flag;const double TOL=1.0e-8;double xx,xmin,fx,fb,fa,bx,ax;int n=num;ncom=n;//pcom_p=new Vec_Dp(n);//xicom_p=new Vec_Dp(n);nrfunc=func;//Vec_Dp &pcom=*pcom_p,&xicom=*xicom_p;double *pcom = pcom_p, *xicom = xicom_p;for (j=0;j<n;j++) {pcom[j]=p[j];xicom[j]=xi[j];}ax=0.0;xx=1.0;mnbrak(ax,xx,bx,fa,fx,fb,f1dim);fret=brent(ax,xx,bx,f1dim,TOL,xmin, flag);for (j=0;j<n;j++) {xi[j] *= xmin;p[j] += xi[j];}//delete xicom_p;//delete pcom_p;}inline bool TOptimization::powell(double *p, double **xi, double ftol, int &iter,double &fret, Reff func){const int ITMAX=500;const double TINY=1.0e-20;int i,j,ibig;double del,fp,fptt,t;int n=num;//Vec_Dp pt(n),ptt(n),xit(n);double *pt, *ptt, *xit;for(i = 0; i < n; ++i){pt = new double [n];ptt = new double [n];xit = new double [n];}fret=func(p);for (j=0;j<n;j++) pt[j]=p[j];for (iter=0;;++iter) {fp=fret;ibig=0;del=0.0;for (i=0;i<n;i++) {for (j=0;j<n;j++) xit[j]=xi[j][i];fptt=fret;linmin(p,xit,fret,func);if (fptt-fret > del) {del=fptt-fret;ibig=i+1;}}if (2.0*(fp-fret) <= ftol*(fabs(fp)+fabs(fret))+TINY) {delete []pt;delete []ptt;delete []xit;return true;}if (iter == ITMAX){delete []pt;delete []ptt;delete []xit;return false;//cerr<<"powell exceeding maximum iterations.";}for (j=0;j<n;j++) {ptt[j]=2.0*p[j]-pt[j];xit[j]=p[j]-pt[j];pt[j]=p[j];}fptt=func(ptt);if (fptt < fp) {t=2.0*(fp-2.0*fret+fptt)*SQR(fp-fret-del)-del*SQR(fp-fptt);if (t < 0.0) {linmin(p,xit,fret,func);for (j=0;j<n;j++) {xi[j][ibig-1]=xi[j][n-1];xi[j][n-1]=xit[j];}}}}}#endif