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﹏ヽ暗。殇╰゛Y 2022-01-15 01:39 192阅读 0赞

[2019独角兽企业重金招聘Python工程师标准>>> ][2019_Python_] ![hot3.png][]

1 #include "StdAfx.h"
     2 #include <iostream>
     3 #include <fstream>
     4 #include <cassert>
     5 #include <string>
     6 
     7 using namespace std; 8 
     9 const int increment = 100; 10 
    11 typedef struct CStashTag{ 12 int size; 13 int quantity; 14 int next; 15 unsigned char* storage; 16 }CStash; 17 
    18 void initialize(CStash* s,int size); 19 void cleanup(CStash* s); 20 int add(CStash* s,const void* element); 21 void* fetch(CStash* s,int index); 22 int count(CStash* s); 23 void inflate(CStash* s,int increase); 24 
    25 void initialize(CStash* s,int sz){ 26     s->size = sz; 27     s->quantity = 0; 28     s->storage = 0; 29     s->next = 0; 30 } 31 
    32 int add(CStash* s,const void* element){ 33     if(s->next >= s->quantity) 34 inflate(s,increment); 35     int startBytes = s->next * s->size; 36     unsigned char* e=(unsigned char*)element; 37     for(int i=0;i<s->size;i++) 38         s->storage[startBytes + i] = e[i]; 39     s->next++; 40     return(s->next -1); 41 } 42 
    43 void* fetch(CStash* s,int index){ 44     assert(0 <= index); 45     if(index >= s->next) 46         return 0; 47     return &(s->storage[index * s->size]); 48 } 49 
    50 int count(CStash* s){ 51     return s->next; 52 } 53 
    54 void inflate(CStash* s,int increase){ 55     assert(increase > 0); 56     int newQuantity = s->quantity + increase; 57     int newBytes = newQuantity * s->size; 58     int oldBytes = s->quantity*s->size; 59     unsigned char* b = new unsigned char[newBytes]; 60     for(int i=0;i<oldBytes;i++) 61         b[i] = s->storage[i]; 62     delete [](s->storage); 63     s->storage = b; 64     s->quantity = newQuantity; 65 } 66 
    67 void cleanup(CStash* s){ 68     if(s->storage != 0) 69 { 70         cout<<"freeing storage"<<endl; 71         delete []s->storage; 72 } 73 } 74 
    75 int main() 76 { 77 CStash intStash,stringStash; 78     int i; 79     char* cp; 80     ifstream in; 81     string line; 82     const int bufsize = 80; 83     initialize(&intStash,sizeof(int)); 84     for(i =0;i<100;i++) 85         add(&intStash,&i); 86     for(i=0;i<count(&intStash);i++) 87         cout<<"fetch(&intStash,"<<i<<")"<<*(int*)fetch(&intStash,i)<<endl; 88     initialize(&stringStash,sizeof(char)*bufsize); 89     in.open("stdafx.cpp"); 90     assert(in); 91     while(getline(in,line)) 92         add(&stringStash,line.c_str()); 93     i=0; 94     while((cp=(char*)fetch(&stringStash,i++))!=0) 95         cout<<"fetch(&stringStash,"<<i<<")"<<cp<<endl; 96     cleanup(&intStash); 97     cleanup(&stringStash); 98     return 0; 99 }

执行结果：

![15165429_QR8U.jpg][]

![15165429_5FoS.jpg][]

转载于:https://my.oschina.net/u/204616/blog/545286

[2019_Python_]: https://my.oschina.net/u/2663968/blog/3061697
[hot3.png]: /images/20220114/11c8106784d648bc82e2b6a838f564e8.png
[15165429_QR8U.jpg]: /images/20220114/aeca9fae281c47c28b2a6ef050228045.png
[15165429_5FoS.jpg]: /images/20220114/ae824e6e57a64d97870784b037f32cbf.png