//samp2.c  -- by tsaiwn@csie.nctu.edu.tw
#include<stdio.h>
#include<stdlib.h>
typedef struct {
   long id;
   char name[9];
   float height;
   double score;
   int rank;  // 名次
} Student;
Student x[999];
double nRand(double avg, double std, double min, double max);
int getData( );
void printData(int n, int flag);
void sort( ) { }
int main( ) {
   int nStu;
   nStu = getData( );
   printData(nStu, 0);
   printf("=== ===\n");
   sort( );
   printData(nStu, 1);
   return 0;
}
int getData( ){
   static char cn[ ][3]={ "趙", "錢", "孫", "李", "陳", "林"};
   static char first[ ][5]= {
      "阿三", "小弟", "三8", "4久", "小五", "阿水", "大華" };
   int cnLen = (sizeof(cn) / sizeof(cn[0]) );
   int firstLen =(sizeof(first) / sizeof(first[0]) );
   int i, k, n;
   long baseID = 9817000;
   k = 5;  // example
   for(i=1; i<= k; ++i) {  // 第 0 個故意不用
      x[i].id = baseID + i;
      n = rand( ) % cnLen;
      strcpy(x[i].name, cn[n]);
      n = rand( ) % firstLen;
      strcat(x[i].name, first[n]);
      x[i].height = nRand(168, 8, 135, 198);  // [135, 198]
   }
   return k;
}
void printData(int n, int flag){
    //印出 n 個人的 data, x[1] .. x[n]; 注意第 0 個故意不用
   // flag == 0 表示不印名次
   int i;
   printf("學 號      姓 名     身高");
   if(flag!=0) printf(" 名次");
   printf("\n");
   for(i=1; i<=n; ++i) {
      printf("%ld ", x[i].id);
      printf("%-9s ", x[i].name);
      printf("%7.2f ", x[i].height); //身高
      if(flag!=0) printf(" %3d", x[i].rank);
      printf("\n");
   }
}
double nRand(double avg, double std, double min, double max){
   // Normal distribution N(avg, std*std)
   int i;
   double ans;
   ans=0.0;
   for(i=1; i<=12; ++i) {
      ans +=  (rand( )%32768L)/32768.0;
   }
   ans -= 6.0;
   ans = avg + ans*std;
   // 調整到規定的 range, 即 [min, max]
   if(ans<min) ans = min;
   if(ans>max) ans = max;
   return ans;
}