競プロで使えるC++プリントデバッグ(Operator Overloading)

map.cpp

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

template<typename T1, typename T2> ostream& operator<<(ostream& s, const map<T1, T2>& m) {
	s << "{" << endl;
	for (typeof(m.begin()) itr = m.begin(); itr != m.end(); ++itr) {
		s << "\t" << (*itr).first << " : " << (*itr).second << endl;
	}
	s << "}" << endl;
	return s;
}

int main(int argc, char** argv) {
	map<int, char> m;
	for (int i = 0; i < 26; ++i) {
		m[i] = 'a' + i;
	}
	cout << m << endl;

	return 0;
}

map.cpp.out

{
        0 : a
        1 : b
        2 : c
        3 : d
        4 : e
        5 : f
        6 : g
        7 : h
        8 : i
        9 : j
        10 : k
        11 : l
        12 : m
        13 : n
        14 : o
        15 : p
        16 : q
        17 : r
        18 : s
        19 : t
        20 : u
        21 : v
        22 : w
        23 : x
        24 : y
        25 : z
}

pair.cpp

#include <iostream>
using namespace std;

template<typename T1, typename T2> ostream& operator<<(ostream& s, const pair<T1, T2>& p) {return s << "(" << p.first << ", " << p.second << ")";}

int main(int argc, char** argv) {
	pair<int, int> p = make_pair(1, 2);
	cout << p << endl;
	return 0;
}

pair.cpp.out

(1, 2)

vector.cpp

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

// vector
template<typename T> ostream& operator<<(ostream& s, const vector<T>& v) {
	int len = v.size();
	for (int i = 0; i < len; ++i) {
		s << v[i]; if (i < len - 1) s << "\t";
	}
	return s;
}

// 2 dimentional vector
template<typename T> ostream& operator<<(ostream& s, const vector< vector<T> >& vv) {
	int len = vv.size();
	for (int i = 0; i < len; ++i) {
		s << vv[i] << endl;
	}
	return s;
}

int main(int argc, char** argv) {
	int N = 10;
	vector<int> a(N);
	for (int i = 0; i < N; ++i) {
		a[i] = i;
	}
	cout << "===== vector<int> =====" << endl;
	cout << a << endl;

	vector< vector<int> > b(N, vector<int>(N));
	for (int i = 0; i < N; ++i) {
		for (int j = 0; j < N; ++j) {
			b[i][j] = i * j;
		}
	}
	cout << endl << "===== vector< vector<int> > =====" << endl;
	cout << b << endl;

	return 0;
}

vector.cpp.out

===== vector<int> =====
0       1       2       3       4       5       6       7       8       9

===== vector< vector<int> > =====
0       0       0       0       0       0       0       0       0       0
0       1       2       3       4       5       6       7       8       9
0       2       4       6       8       10      12      14      16      18
0       3       6       9       12      15      18      21      24      27
0       4       8       12      16      20      24      28      32      36
0       5       10      15      20      25      30      35      40      45
0       6       12      18      24      30      36      42      48      54
0       7       14      21      28      35      42      49      56      63
0       8       16      24      32      40      48      56      64      72
0       9       18      27      36      45      54      63      72      81