Just look at the others made a topic in the group

 This is a sort + string handling the subject, the difficulty belongs to the PAT B, five questions in the third question.

Analysis: lexicographic order is the order of the string in the dictionary. E.g,

1. "A" is lexicographically less than "a";

2. "A" is lexicographically less than "b";

3. "Aa" lexicographic order is less than "aaaa"

4. "Aaaa" is lexicographically smaller than "aab" dictionary order, from the most significant bit here, a comparison of a character's character.

5. "Aa" lexicographic order is less than "aa"

#include<iostream>
#include<algorithm>
using namespace std;

bool cmp(string a,string b) {
    //计算单词ASCII值，并转小写单词
    int sum1 = 0,sum2 = 0;
    for(int i = 0 ; i < a.size(); ++i) {
        sum1 += a[i];
        a[i] = tolower(a[i]);
    }
    for(int i = 0 ; i < b.size(); ++i) {
        sum2 +=B [I]; 
        B [I] = tolower (B [I]); 
    } 
    IF (! A = B) return A <B; // Comparative lowercase words 
    the else  return SUM1 <SUM2; // the same word, it is more ASCII and 
} 

int main () {
     int n;
     String STR [ 100 ]; 
    CIN >> n;
     for ( int I = 0 ; I <n; ++ I) // n words input 
        CIN >> STR [I]; 
    Sort (STR, STR + n-, CMP); // the converted into lowercase words lexicographic, the original word ASCII code，对单词排序
    for(int i = 0; i < n;++i){
        if(i > 0) printf(" ");
        cout<<str[i];
    }
    return 0;
}