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Absolute positioning in a cout listing in C ++?

How do you get “absolutely positioned” columns with cout that align text and align correction numbers?

#include <iostream>
#include <iomanip>
using namespace std;

struct Human {
    char name[20];
    char name2[20];
    char name3[20];
    double pts;
};

int main() {
    int i;
    Human myHumen[3] = {
        {"Mr", "Alan", "Turing", 12.25},
        {"Ms", "Ada", "Lovelace", 15.25},
        {"Sir",  "Edgar Allan", "Poe", 45.25}
    };
    cout << "Name1" << setw(22) << "Name2" << setw(22) << "Name3" << setw(22) << "Rating" <<endl;
    cout << "-----------------------------------------------------------------------\n";
    for(i = 0; i < 3; i++) {
        cout << myHumen[i].name << setw(22) << myHumen[i].name2 << setw(22) << myHumen[i].name3 << setw(20) << myHumen[i].pts << endl;
    }//this didn't do nice printouts, with leftalign for text and rightalign with numbers
}
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2 answers

You use the "left" and "right" manipulators:

cout << std::left  << std::setw(30) << "This is left aligned"
     << std::right << std::setw(30) << "This is right aligned";

Example with text + numbers:

typedef std::vector<std::pair<std::string, int> > Vec;
std::vector<std::pair<std::string, int> > data;
data.push_back(std::make_pair("Alan Turing", 125));
data.push_back(std::make_pair("Ada Lovelace", 2115));

for(Vec::iterator it = data.begin(), e = data.end(); it != e; ++it)
{
    cout << std::left << std::setw(20) << it->first
         << std::right << std::setw(20) << it->second << "\n";
}

What prints:

Alan Turing                          125
Ada Lovelace                        2115
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This will be a little unpopular, but you can just use printf for this quick program. Formatting strings are easier to understand and use (someone looking for both iostreams and printf).

#include <cstdio>
#include <iostream>
#include <iomanip>
#include <string>

struct Human {
  char name[20];   // consider using std::string
  char name2[20];
  char name3[20];
  double pts;
};

int main() {
  using namespace std;
  Human people[3] = {
    {"Mr", "Alan", "Turing", 12.25},
    {"Ms", "Ada", "Lovelace", 15.25},
    {"Sir",  "Edgar Allan", "Poe", 45.25}
  };
  printf("%-22s%-22s%-22s%20s\n", "Name1", "Name2", "Name3", "Rating");
  cout << string(22 * 3 + 20, '-') << '\n';
  for (int i = 0; i < 3; i++) {
    Human const& h = people[i];
    printf("%-22s%-22s%-22s%20f\n", h.name, h.name2, h.name3, h.pts);
  }
  return 0;
}

( , . std:: sync_with_stdio) cout printf, (-Wall gcc).

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