#include<iostre am>
using namespace std;
int main(void){
const pair<const char*,const char*arr[]={
pair<const char*,const char*>("1","1") ,
pair<const char*,const char*>("12","12 "),
pair<const char*,const char*>("123","1 23"),
pair<const char*,const char*>("1234"," 1234"),
pair<const char*,const char*>("12345", "12345"),
};
cout<<sizeof(ch ar)<<endl;
cout<<sizeof(ar r[0])<<endl;
cout<<sizeof arr<<endl;
cout<<sizeof(ar r)/sizeof(arr[0])<<endl;
return 0;
}
gives me :
1
8 <- ????? Why ????
40
5
4  12255 
onkar wrote:
#include<iostre am>
using namespace std;
int main(void){
const pair<const char*,const char*arr[]={
pair<const char*,const char*>("1","1") ,
pair<const char*,const char*>("12","12 "),
pair<const char*,const char*>("123","1 23"),
pair<const char*,const char*>("1234"," 1234"),
pair<const char*,const char*>("12345", "12345"),
};
cout<<sizeof(ch ar)<<endl;
cout<<sizeof(ar r[0])<<endl;
cout<<sizeof arr<<endl;
cout<<sizeof(ar r)/sizeof(arr[0])<<endl;
return 0;
}
gives me :
1
8 <- ????? Why ????
2*sizeof(char*) ?
--
Ian Collins.
onkar wrote:
#include<iostre am>
using namespace std;
int main(void){
const pair<const char*,const char*arr[]={
pair<const char*,const char*>("1","1") ,
pair<const char*,const char*>("12","12 "),
pair<const char*,const char*>("123","1 23"),
pair<const char*,const char*>("1234"," 1234"),
pair<const char*,const char*>("12345", "12345"),
Have a look at std::make_pair.
};
cout<<sizeof(ch ar)<<endl;
cout<<sizeof(ar r[0])<<endl;
cout<<sizeof arr<<endl;
cout<<sizeof(ar r)/sizeof(arr[0])<<endl;
return 0;
}
gives me :
1
8 <- ????? Why ????
Why not? What did you expect?
40
5
Hi,
sizeof of STL containers does not return the size of the contained
object - sizeof vector<charcont aing 100 chars is not 100. You need to
check your STL implementation of pair to see why it is returning 8.
Thanks and regards
Sonison James
onkar wrote:
#include<iostre am>
using namespace std;
int main(void){
const pair<const char*,const char*arr[]={
pair<const char*,const char*>("1","1") ,
pair<const char*,const char*>("12","12 "),
pair<const char*,const char*>("123","1 23"),
pair<const char*,const char*>("1234"," 1234"),
pair<const char*,const char*>("12345", "12345"),
};
cout<<sizeof(ch ar)<<endl;
cout<<sizeof(ar r[0])<<endl;
cout<<sizeof arr<<endl;
cout<<sizeof(ar r)/sizeof(arr[0])<<endl;
return 0;
}
gives me :
1
8 <- ????? Why ????
40
5
In message <11************ *********@b28g2 000cwb.googlegr oups.com>, so***********@g mail.com writes
[Please don't top-post. Rearranged]
>onkar wrote:
>#include<iostr eam>
using namespace std;
int main(void){
const pair<const char*,const char*arr[]={
pair<const char*,const char*>("1","1") ,
pair<const char*,const char*>("12","12 "),
pair<const char*,const char*>("123","1 23"),
pair<const char*,const char*>("1234"," 1234"),
pair<const char*,const char*>("12345", "12345"),
};
cout<<sizeof(ch ar)<<endl;
cout<<sizeof(ar r[0])<<endl;
cout<<sizeof arr<<endl;
cout<<sizeof(ar r)/sizeof(arr[0])<<endl;
return 0;
}
gives me :
1
8 <- ????? Why ????
40
5
sizeof of STL containers does not return the size of the contained
object - sizeof vector<charcont aing 100 chars is not 100.
std::pair isn't a "container" the way vector is. It's just a templated
2-element structure.
>You need to
check your STL implementation of pair to see why it is returning 8.
What would you expect the size of the following to be?
struct {
const char * first;
const char * second;
};
--
Richard Herring This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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