There are two points to define such a question:
1. Create a table: index the character with an array subscript. Note that if the character is returned to a number:
Int Index = (STR [I]> = '0' & STR [I] <= '9 ')? (STR [I]-'0'-radix) :( STR [I]-'A'-radix + 10 );
2. Pay attention to whether the low position is in front of the high position. If the first position isLow * Radix ^ IYou can.
3. Calculate the number of Radix hexadecimal arrays in one bits...
This is mainly troublesome...
#include <assert.h>#include <algorithm>#include <vector>using namespace std;const int radix = 4;string base = "";string compress(const vector<int>& arr) { string res = ""; int i, j, size = arr.size(), left, bits; for (i = 1, j = 0; i*radix + radix < 36; i *= radix, ++j); bits = j; left = size - size / bits * bits; size = size / bits * bits; for (char ch = '0'; ch <= '9'; ++ch) base.push_back(ch); for (char ch = 'a'; ch <= 'z'; ++ch) base.push_back(ch); for (i = 0; i < size; i += bits) { int index = 0, t = 1; for (j = 0; j < bits; ++j) { index = index + arr[i+j]*t; t *= radix; } res.push_back(base[radix+index]); } for (i = 0; i < left; ++i) res.push_back(arr[size+i]+'0'); return res; }vector<int> depress(const string& str) { int len = str.length(), i = 0, j, bits; for (i = 1, j = 0; i*radix + radix< 36; i *= radix, ++j); bits = j; vector<int> res; for (i = 0; i < len; ++i) { if (str[i]-'0' >= 0 && str[i]-'0' < radix) res.push_back(str[i]-'0'); else { int index = (str[i] >= '0' && str[i] <= '9') ? (str[i]-'0'-radix):(str[i]-'a'-radix + 10); for (j = 0; j < bits; ++j) { res.push_back(index%radix); index = index/radix; } } } return res;} int main() { int arr[] = {0,1,2,2,2,2,1,1,1,2,0,0,0,0,0,1}; vector<int> vec(arr, arr+sizeof(arr) / sizeof(int)); string str = compress(vec); vector<int> res = depress(str); return 0;}