76 lines
1.4 KiB
C++
76 lines
1.4 KiB
C++
/* pingala.cpp
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* Created: 2024-09-15
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* Author: Aryadev Chavali
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*/
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#include <cstdio>
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#include <iostream>
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#include <sstream>
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#include <string>
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#include <vector>
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std::vector<std::string> generate_triangle(const size_t depth)
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{
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std::vector<std::string> levels;
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std::vector<size_t> items;
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std::stringstream ss;
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levels.reserve(depth);
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items.resize(depth * depth);
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#define AT(i, j) items[((i) * depth) + (j)]
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AT(0, 0) = 1;
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levels.push_back("1");
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for (size_t i = 1; i < depth; ++i)
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{
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AT(i, 0) = 1;
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ss << "1 ";
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for (size_t j = 1; j < i; ++j)
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{
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AT(i, j) = AT(i - 1, j - 1) + AT(i - 1, j);
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ss << AT(i, j) << " ";
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}
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AT(i, i) = 1;
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ss << "1";
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levels.push_back(ss.str());
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ss.str(std::string{});
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}
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#undef AT
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return levels;
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}
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void usage(FILE *fp)
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{
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fprintf(fp, "Usage: pingala.out [depth]\n"
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"\tdepth: Depth of triangle generated\n");
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}
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int main(int argc, char *argv[])
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{
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// Variable declarations
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std::vector<std::string> levels;
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int depth = 0;
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if (argc < 2)
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goto error;
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depth = std::stoi(argv[1]);
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if (depth <= 0)
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goto error;
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levels = generate_triangle(depth);
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for (const auto &level : levels)
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{
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for (size_t i = 0;
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i < (levels[levels.size() - 1].size() - level.size()) / 2; ++i)
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{
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printf(" ");
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}
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printf("%s\n", level.c_str());
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}
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return 0;
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error:
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usage(stderr);
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return 1;
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}
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