Megaderp

output.txt

C:\Users\billy\Desktop>cl /EHsc /W4 /WX .\test.cpp && .\test.exe
Microsoft (R) C/C++ Optimizing Compiler Version 19.20.27607.1 for x86
Copyright (C) Microsoft Corporation.  All rights reserved.

test.cpp
Microsoft (R) Incremental Linker Version 14.20.27607.1
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:test.exe
test.obj
actual:
{0, 0}
{1, 0}
{2, 0}
{3, 4}
{3, 0}
{3, 1}
{3, 2}
{3, 3}
{4, 0}
{5, 0}
{6, 0}
expected:
{0, 0}
{1, 0}
{2, 0}
{3, 0}
{3, 1}
{3, 2}
{3, 3}
{3, 4}
{4, 0}
{5, 0}
{6, 0}
fail

test.cpp

#include <map>
#include <algorithm>
#include <stdio.h>

using namespace std;

void print_map(const std::multimap<int, int>& m) {
    for (const pair<const int, int>& p : m) {
        printf("{%d, %d}\n", p.first, p.second);
    }
}

int main() {
    multimap<int, int> m{
        {0, 0},
        {1, 0},
        {2, 0},
        {3, 1},
        {3, 2},
        {3, 3},
        {4, 0},
        {5, 0},
        {6, 0},
    };

    // Standard: The element is inserted as close as possible to the position just prior to p.
    m.emplace_hint(next(m.begin()), 3, 0); // should insert at the beginning of the 3s
    m.emplace_hint(prev(m.end()), 3, 4); // should insert at the end of the 3s

    const multimap<int, int> expected{
        {0, 0},
        {1, 0},
        {2, 0},
        {3, 0},
        {3, 1},
        {3, 2},
        {3, 3},
        {3, 4},
        {4, 0},
        {5, 0},
        {6, 0},
    };

    puts("actual:");
    print_map(m);

    puts("expected:");
    print_map(expected);

    puts(equal(m.begin(), m.end(), expected.begin(), expected.end()) ? "pass" : "fail");
}