Demo of getter to grab data from array of structs.

getallpeople.solpp

pragma soliditypp ^0.4.3;

// modification of answer from
// https://stackoverflow.com/questions/48877910/how-can-i-return-an-array-of-struct-in-solidity
// for soliditypp

contract Project
{
    struct Person {
        address addr;
        uint bal;
    }

    Person[] people;

    onMessage addPerson(address addr, uint bal){
        people.push(Person(addr, bal));
    }

    // returns selected people
    getter getPeople(uint[] calldata indexes) returns (address[] memory addr, uint[] memory bal) {
        address[] memory addrs = new address[](indexes.length);
        uint[]    memory bals = new uint[](indexes.length);

        for (uint i = 0; i < indexes.length; i++) {
            Person storage person = people[indexes[i]];
            addrs[i] = person.addr;
            bals[i] = person.bal;
        }

        return (addrs, bals);
    }

    // returns all people
    getter getAllPeople() returns (address[] memory addr, uint[] memory bal) {
        address[] memory addrs = new address[](people.length);
        uint[]    memory bals = new uint[](people.length);

        for (uint i = 0; i < people.length; i++) {
            Person storage person = people[i];
            addrs[i] = person.addr;
            bals[i] = person.bal;
        }

        return (addrs, bals);
    }
}