63 lines
1.9 KiB
Zig
63 lines
1.9 KiB
Zig
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//
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// We've seen that the 'for' loop can let us perform some action
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// for every item in an array or slice.
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//
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// More recently, we discovered that it supports ranges to
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// iterate over number sequences.
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//
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// This is part of a more general capability of the `for` loop:
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// looping over one or more "objects" where an object is an
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// array, slice, or range.
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//
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// In fact, we *did* use multiple objects way back in Exercise
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// 016 where we iterated over an array and also a numeric index.
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// It didn't always work exactly this way, so the exercise had to
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// be retroactively modified a little bit.
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//
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// for (bits, 0..) |bit, i| { ... }
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//
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// The general form of a 'for' loop with two lists is:
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//
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// for (list_a, list_b) |a, b| {
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// // Here we have the first item from list_a and list_b,
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// // then the second item from each, then the third and
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// // so forth...
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// }
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//
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// What's really beautiful about this is that we don't have to
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// keep track of an index or advancing a memory pointer for
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// *either* of these lists. That error-prone stuff is all taken
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// care of for us by the compiler.
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//
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// Below, we have a program that is supposed to compare two
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// arrays. Please make it work!
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//
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const std = @import("std");
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const print = std.debug.print;
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pub fn main() void {
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const hex_nums = [_]u8{ 0xb, 0x2a, 0x77 };
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const dec_nums = [_]u8{ 11, 42, 119 };
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for (hex_nums, ???) |hn, ???| {
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if (hn != dn) {
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std.debug.print("Uh oh! Found a mismatch: {d} vs {d}\n", .{ hn, dn });
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return;
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}
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}
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std.debug.print("Arrays match!\n", .{});
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}
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//
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// You are perhaps wondering what happens if one of the two lists
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// is longer than the other? Try it!
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//
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// By the way, congratulations for making it to Exercise 100!
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//
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// +-------------+
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// | Celebration |
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// | Area * * * |
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// +-------------+
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//
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// Please keep your celebrating within the area provided.
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