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# include <bits/stdc++.h>
using namespace std ;
const int N = 256 ;
//桶
int b [ N ] ; //0 ~ 255
//将一个16进制的灰阶转为一个整数, 方便用来当数组的下标索引值
int toDec ( char a , char b ) {
int res = 0 ;
if ( a > = ' A ' & & a < = ' F ' )
res + = ( a - ' A ' + 10 ) * 16 ;
else
res + = ( a - ' 0 ' ) * 16 ;
if ( b > = ' A ' & & b < = ' F ' )
res + = b - ' A ' + 10 ;
else
res + = b - ' 0 ' ;
return res ;
}
//将一个十进制的灰阶值[0,255]转化成十六进制[0,FF]
string toHex ( int x ) {
int a = x % 16 ; // 0 ~ 15
int b = x / 16 ; //
char c1 ;
if ( a > = 10 )
c1 = ' A ' + a - 10 ;
else
c1 = ' 0 ' + a ;
char c2 ;
if ( b > = 10 )
c2 = ' A ' + b - 10 ;
else
c2 = ' 0 ' + b ;
string res ;
res . push_back ( c2 ) ;
res . push_back ( c1 ) ;
return res ;
}
//原始的字符串数组
vector < string > q ;
//结构体,用来把桶中的灰阶按数量排序用的
struct Node {
int id ; //数组下标
int cnt ; //个数
const bool operator < ( const Node & b ) const {
if ( cnt = = b . cnt )
return id < b . id ;
return cnt > b . cnt ;
}
} ;
vector < Node > vec ; //需要把bucket组装成Node放到数组p中, 才能使用结构体排序吧
int main ( ) {
int n ;
cin > > n ; //有n行数据组成了图像
for ( int i = 1 ; i < = n ; i + + ) {
string s ;
cin > > s ;
q . push_back ( s ) ; //原始数组
for ( int j = 0 ; j < s . size ( ) ; j + = 2 ) {
char c1 = s [ j ] , c2 = s [ j + 1 ] ;
int k = toDec ( c1 , c2 ) ; //灰阶对应的数组位置
b [ k ] + + ;
}
}
//找出前16位使用频率高的灰阶
//排序,按什么排序呢?
//1、按数量, 数量多的在前
//2、如果数量一样多呢?桶中索引小的在前
for ( int i = 0 ; i < = 255 ; i + + ) {
if ( b [ i ] ) //数量大于0的才有意义
vec . push_back ( { i , b [ i ] } ) ;
}
//使用自定义排序方法排序
sort ( vec . begin ( ) , vec . end ( ) ) ;
for ( int i = 0 ; i < n ; i + + ) { //枚举每个原始字符串, 每2个一组, 判断这个小串应该与尺子数组中的哪一个更接近
for ( int j = 0 ; j < q [ 0 ] . size ( ) ; j + = 2 ) {
char c1 = q [ i ] [ j ] , c2 = q [ i ] [ j + 1 ] ;
//计算ab组装出的短串与上面vec中的前16个哪个距离最短
int x = toDec ( c1 , c2 ) ;
int mi = INT_MAX ;
int mi_p = 0 ;
for ( int k = 0 ; k < min ( 16 , vec . size ( ) ) ; k + + ) { //16是有风险的, 因为可能没有16个那么多
if ( mi > abs ( vec [ k ] - x ) ) {
mi = abs ( vec [ k ] - x ) ;
mi_p = k ;
}
}
//mi_p [0,255] -> 十六进制
//将当前的a,b这个值修改为mi_p这个灰阶值
cout < < toHex ( mi_p ) ;
}
}
return 0 ;
}