December 2018
Intermediate to advanced
222 pages
6h 6m
English
Content preview from Blockchain Quick Start Guide
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Mapping
Mappings act as hash tables that consist of key types and corresponding value type pairs. Here is an example, as follows:
pragma solidity ^0.4.24;contract StudentScore { struct Student { uint score; string name; } mapping (address => Student) studtents; address[] public studentAccts; function setStudent(address _address, uint _score, string _name) public { Student storage studtent = studtents[_address]; studtent.score = _score; studtent.name = _name; studentAccts.push(_address) -1; } function getStudents() view public returns(address[]) { return studentAccts; } function getStudent(address _address) view public returns (uint, string) { return (studtents[_address].score, studtents[_address].name); } function countStudents() view public ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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