69 lines
1.7 KiB
C++
69 lines
1.7 KiB
C++
#include <iostream>
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#include <string>
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/**
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* 6. Zigzag Conversion
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* The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)
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* P A H N
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* A P L S I I G
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* Y I R
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* And then read line by line: "PAHNAPLSIIGYIR"
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* Write the code that will take a string and make this conversion given a number of rows:
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* string convert(string s, int numRows);
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*/
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class Solution {
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public:
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static std::string convert(const std::string& s, int numRows) {
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int n = s.length();
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if (n == 1 || numRows == 1)
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return s;
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int interval = (numRows << 1) - 2;
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int spaceH = interval - numRows;
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std::string ret;
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// Line 0
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for (int i = 0; i < n; i += interval) {
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// if (i)
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// ret += std::string(spaceH, ' ');
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ret.push_back(s[i]);
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}
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// ret.push_back('\n');
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// Line [1, n)
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for (int i = 1; i < numRows - 1; ++i) {
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for (int j = i; j < n; j += interval) {
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ret.push_back(s[j]);
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// Check if this group's counterpart is OK.
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int cp = (interval - j % interval) + (j / interval * interval);
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if (cp < n) {
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// int spaceL = cp % interval - numRows;
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// int spaceR = spaceH - spaceL - 1;
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// ret += std::string(spaceL, ' ');
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ret.push_back(s[cp]);
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// if (spaceR && cp / interval * interval + interval + j % interval < n)
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// ret += std::string(spaceR, ' ');
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}
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}
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// ret.push_back('\n');
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}
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// Line n
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for (int i = numRows - 1; i < n; i += interval) {
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// if (i / interval)
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// ret += std::string(spaceH, ' ');
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ret.push_back(s[i]);
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}
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return ret;
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}
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};
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int main() {
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std::cout << Solution::convert("ABCDEFGHIJKLMNOPQRSTUVWXYZ", 6);
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return 0;
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}
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