c++ - How can I use C++11's range-based for loop to output data in a table? -


this code:

#include <iostream> #include <iomanip> #include <array> using namespace std;  int main() {     // array< int, 5 > n;     int n [ 5 ] = { 2, 4, 6, 8, 10};      cout << "element" << setw(13) << "value" << endl;      ( int j : n )     {         cout << setw(7) << j << setw(13) << n[ j ] << endl;     } }

it produced output:

element        value       2            6       4           10       6  -1078585116       8  -1217581056      10            0

while expected output:

element        value       1            2       2            4       3            6       4            8       5           10

i've tried changing small things, didn't work. did wrong?

if need index when better use ordinary loop instead of range based loop. example

int main() {     // array< int, 5 > n;     int n [ 5 ] = { 2, 4, 6, 8, 10};      cout << "element" << setw(13) << "value" << endl;      ( size_t = 0; < sizeof( n ) / sizeof( *n ); i++ )     {         cout << setw(7) << + 1 << setw(13) << n[ ] << endl;     } }

if want use range based loop need declare auxiliary count before loop. example

int main() {     // array< int, 5 > n;     int n [ 5 ] = { 2, 4, 6, 8, 10};      cout << "element" << setw(13) << "value" << endl;      size_t = 0;      ( int : n )     {         cout << setw(7) << ++i << setw(13) << << endl;     } }

as code using elements of array indices in it

for ( int j : n ) {     cout << setw(7) << j << setw(13) << n[ j ] << endl;                       ^^^                ^^^^^                      element of n       using element of n index }

Comments

Post a Comment

Popular posts from this blog

java - Spring Data JPA: Why findOne(id) executing delete query internally? -

i have 1 application using @manytomany annotation link 2 different entities 1 parent entity. not sure if have implemented properly. when execute .findone() on parent entity's repository find it, @ first fetch data along executing delete queries internally delete record mapping table (a table jpa creates after adding @manytomany annotation.). following generated sql queries , code snippet: java class @entity @table(name = "inventory") public class inventory { @id long id; // many other properties @manytomany(fetch=fetchtype.lazy) private list<stream> streams; @manytomany(fetch=fetchtype.lazy) private list<subject> subjects; } there no other annotation i've put in stream , subject entity class link inventory class. when run app, create following tables: inventory stream subject inventory_stream inventory_subject (inventory_stream , inventory_subject, 2 tables created automatically, don't k...
Read more

python - Mongodb How to add addtional information when aggregating? -

i beginner , wrote line pipeline works, wanna add other information output, screen name , or number of tweets.i tried add under $group gave me syntax error everytime here pipeline: def make_pipeline(): # complete aggregation pipeline pipeline = [ { '$match': { "user.statuses_count": {"$gt":99 }, "user.time_zone": "brasilia" } }, { "$group": { "_id": "$user.id", "followers": { "$max": "$user.followers_count" } } }, { "$sort": { "followers": -1 } }, { "$limit" : 1 } ]; i using on example : { "_id" : objectid("5304e2e3cc9e684aa98bef97"), "text" : "first week of school on :p", "in_reply_to_status_id" : null, "retweet_count" : null, ...
Read more

java - Incorrect order of records in M-M relationship in hibernate -

Image
i have 4 records in bridge table in mysql database. using @manytomany in hibernate, accurate order of employees incorrect incorrect of projects. following required material figure out doing mistake. this source. @entity @table(name="project") public class projectbean { @id @generatedvalue @column(name="project_id") private int projectid; @column(name="title") private string projecttitle; @manytomany(mappedby="projects") private collection<employeebean> employees; public projectbean() { employees = new arraylist<employeebean>(); } //getters & setters } @entity @table(name="employee") public class employeebean { @id @generatedvalue @column(name="employee_id") private int employee_id; @column(name="first_name") private string ...
Read more