basic array subprograms

00.basicArraySubprograms.cpp

// 00.basicArraySubprograms.cpp
// juanfc 2024-11-04
//

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

// consts
const int N=5;

// types
typedef array<int,N> TVec;

int main()
{
    void printArr(TVec a);
    void initArr0(TVec& a);
    void readArr(TVec& a);
    TVec readArr(void);
    int  sumArr(TVec a);
    bool isIn(TVec a, int x);
    int  indexOf(TVec a, int x);
    int  count(TVec a, int x);
    bool anyReps(TVec a);
    bool anyReps2(TVec a);
    int  findPosFirstMax(TVec a);

    cout << "No initialised: " << endl;
    TVec z;
    printArr(z);
    cout << endl;

    cout << "Input the " << N << " elements of an array" << endl;
    TVec v = {{1,4,-3,4,5}};    //readArr();

    cout << "Array read: " << endl;
    printArr(v);
    cout << endl;

    cout << "sumArr: " << sumArr(v) << endl;
    cout << endl;

    cout << "isIn(v, 5): " << isIn(v, 5) << endl;
    cout << "isIn(v, 10): " << isIn(v, 10) << endl;
    cout << endl;

    cout << "indexOf(v, 5): " << indexOf(v, 5) << endl;
    cout << "indexOf(v, 10): " << indexOf(v, 10) << endl;
    cout << endl;

    cout << "count(v, 4): " << count(v, 4) << endl;
    cout << "count(v, 10): " << count(v, 10) << endl;
    cout << endl;

    cout << "anyReps(v): " << anyReps(v) << endl;
    cout << "anyReps2(v): " << anyReps2(v) << endl;
    cout << endl;

    cout << "findPosFirstMax(v): " << findPosFirstMax(v) << endl;
    cout << endl;


    return 0;
}

// subprogram bodies

int  findPosFirstMax(TVec a)
{
    int p = 0;
    for (int i = 0; i < a.size(); ++i)
        if (a[i] > a[p])
            p = i;
    return p;
}

bool isIn(TVec a, int x)
{
    int i = 0;
    while (i < a.size() and a[i] != x)
        ++i;
    return i < a.size();
}

int  indexOf(TVec a, int x)
{
    int i = 0;
    while (i < a.size() and a[i] != x)
        ++i;

    int r;
    if (i < a.size())
        r = i;
    else
        r = -1;
    return r;
}

int  count(TVec a, int x)
{
    int cnt = 0;

    for (int i = 0; i < a.size(); ++i)
        if (a[i] == x)
            ++cnt;

    return cnt;
}

bool anyReps(TVec a)
{
    bool thereIsARep = false;
    int i = 0;
    while ( i < N-1 and not thereIsARep) {
        int j = i + 1;
        while ( j < N and not thereIsARep) {
            thereIsARep =  a[i] == a[j];
            j++;
        }
        i++;
    }
    return thereIsARep;
}

bool anyReps2(TVec a)
{
    int i = 0;
    int j;
    do {
        j = i + 1;
        while ( j < N and a[i] != a[j])
            ++j;
        i++;
    } while ( j >= N and i < N-1);

    return j < N;
}

int  sumArr(TVec a)
{
    int s = 0;
    for (int i = 0; i < a.size(); ++i)
        s += a[i];
    return s;
}

TVec readArr(void)
{
    TVec r;
    for (int i = 0; i < r.size(); ++i)
        cin >> r[i];
    return r;
}

void readArr(TVec& a)
{
    for (int i = 0; i < a.size(); ++i)
        cin >> a[i];
}

void printArr(TVec a)
{
    for (int i = 0; i < a.size(); ++i)
        cout << a[i] << " ";
}

void initArr0(TVec& a)
{
    for (int i = 0; i < a.size(); ++i)
        a[i] = 0;
}