poj-1002:487-3279 detailed 1: Heap sorting method

> Analysis>> The difficulty lies in the speed of sorting>> sorting algorithm to consider a lot of duplicates, no duplicates two cases>> of course, because the subject of memory consumption is not high, you can also do not use sorting 

> General Ideas

>> Save phone numbers in the order you enter them first>> use heap sorting for all numbers>> number of consecutive frequency output frequencies greater than 1 after sorting according to the number > Input Conversion>> the mapping of letters to numbers has been defined in detail, so it is recommended to use a faster mapping table > Storage Format>> because it involves sorting comparisons, it is recommended to store the phone number as an integer, without using a string > Sort>> It is recommended to use heap sorting, considering that there may be many duplicate numbers>> Quick Sort efficiency soles when too many duplicates are processed > attached Code

/*---------------------------------* Heap sequencing, output calculation occurs at the frequency *---------------------------------*/#include"stdio.h"#include"string.h"#include"stdlib.h"/*letter-to-number mapping table*/Const intmap[ -] = {    2,2,2,/*A, B, C*/    3,3,3,/*D, E, F*/    4,4,4,/*G, H, I*/    5,5,5,/*J, K, L*/    6,6,6,/*M, N, O*/    7,0,7,7,/*P, Q, R, S*/    8,8,8,/*T, U, V*/    9,9,9,/*W, X, Y*/    0           /*Z*/} ;/*store all the phone numbers that appear*/inttelenum[100000] = {0} ;voidExchangeint*P1,int*p2) {    intTMP = *P1; *P1 = *P2; *P2 =tmp;}/*maintain the nature of the maximum heap (non-recursive)*/voidMaxheapify (int*pstart,intSizeinti) {    intleft =0 ; intright =0 ; intlargest =0 ; Largest=i;  Do{i=largest; Left=2* i +1 ; Right=2* i +2 ; if(Left < size && Pstart[left] >Pstart[largest]) largest=Left ; if(Right < size && Pstart[right] >Pstart[largest]) largest=Right ; if(Largest! =i) Exchange (&pstart[i], &Pstart[largest]); } while(Largest! =i);}/*Heap Sort*/voidSortint*pstart,intsize) {    inti =0 ;  for(i = size/2-1; I >=0; i--) maxheapify (pstart, size, i);  for(i = size-1; i >0; i--) {Exchange (&pstart[0], &Pstart[i]); Maxheapify (Pstart, I,0) ; }    }intMainvoid){    intn =0 ; Chars[ -] = {0} ; intnum =0 ; inti =0, j =0 ; intCount =0 ; CharFlag =0 ; scanf ("%d", &N);  for(i =0; I < n; i++) {memset (s),0,sizeof(s)); scanf ("%s", s); /*Convert a phone number to an integer type*/Num=0 ;  for(j =0; J <sizeof(s); J + +)        {            if(0==S[j]) Break ; if('Q'= = S[j] | |'Z'==S[j])Continue ; if(S[j] >='A'&& S[j] <='Z') Num= num *Ten+ Map[s[j]-'A'] ; if(S[j] >='0'&& S[j] <='9') Num= num *Ten+ S[j]-'0' ; } Telenum[i]=num;    } sort (Telenum, n); Flag=0 ; Num= telenum[0] ; Count=1 ;  for(i =1; I < n; i++)    {        if(Telenum[i]! =num) {            if(Count >1) {flag=1 ; printf ("%03d-%04d%d\r\n", NUM/10000, Num%10000, Count); } num=Telenum[i]; Count=1; }        ElseCount++ ; }    if(Count >1) {flag=1 ; printf ("%03d-%04d%d\r\n", NUM/10000, Num%10000, Count); }    if(0==flag) printf ("No duplicates.\r\n") ; return 0 ;}

poj-1002:487-3279 detailed 1: Heap sorting method