排序結構和數組

Question

我的任務是與名，得分爲文件的遊戲讀取（文件看起來像）

5 
John Doe 200 
Chris Brown 340 
Chris Brown 320 
John Smith 300 
John Doe 600 

，並打印出的字母順序最高的名字（姓）來自那個人的分數。因此，輸出將類似於：

Chris Brown 340 
John Doe 600 
John Smith 300 

我想通了，如何排序和打印從最高到最低，但我失去了對如何從每個人打印出剛中得分最高的分數......任何幫助將不勝感激！

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

struct playerscore 
{ 
    string first, last; 
    int score; 
}; 

bool score(playerscore a, playerscore b); 
void selectionsort(playerscore *A, int n); 

int main() 
{ 
    string file; 
    int n; 
    cin >> file; 
    ifstream fin(file.c_str()); 
    fin >> n; 

    // read in the names and the scores in the form of struct playerscore 
    playerscore *A = new playerscore[n]; 
    for(int i = 0; i < n; i++) 
     fin >> A[i].first >> A[i].last >> A[i].score; 

    // sort the data 
    selectionsort(A, n); 

    // print in sorted order 
    for(int i = 0; i < n; i++) 
     cout << A[i].score << " "; 
    cout << endl; 

    return 0; 
} 

bool before(playerscore a, playerscore b) 
{ 
    return a.score > b.score; 
} 
void selectionsort(playerscore *A, int n) 
{ 
    for(int length = n; length > 1; length--) 
    { 
     //find imax, index of largest 
     int imax = 0, i; 
     for(i = 1; i < length; i++) 
      if(before(A[imax], A[i])) 
       imax = i; 
     // swap A[imax] and the last element 
     playerscore temp = A[imax]; 
     A[imax] = A[length-1]; 
     A[length-1] = temp; 
    } 
} 

Answer 1

正如之前指出的那樣，由於這是一項任務，我決定重寫代碼，現在應該看起來像這樣。

1. 排序基於所述分數

2. 排序陣列基於字母順序

3. 打印唯一條目

   #include <iostream> 
   #include <fstream> 
   using namespace std; 
   
   struct playerscore 
   { 
       string first, last; 
       int score; 
   }; 
   
   bool score(playerscore a, playerscore b); 
   void selectionsort(playerscore *A, int n); 
   
   int main() 
   { 
       string file; 
       int n; 
       cin >> file; 
       ifstream fin(file.c_str()); 
       fin >> n; 
   
       // read in the names and the scores in the form of struct playerscore 
       playerscore *A = new playerscore[n]; 
       for (int i = 0; i < n; i++) 
        fin >> A[i].first >> A[i].last >> A[i].score; 
   
       // sort the data 
       selectionsort(A, n); 
       // sort alphabetically and print unique entries 
       for (int i=0; i<n-1; i++) 
       { 
        for (int j=i+1; j<n; j++) 
        { 
         if (A[j].last <= A[i].last && A[j].first < A[i].first) 
         { 
          playerscore tmp = A[i]; 
          A[i] = A[j], A[j] = tmp; 
         } 
       } 
   
       playerscore max; 
       int j = 0; 
       for (int i=0; j+i<n; i++) 
       { 
        max.score = -1; 
   
        while (j+i<n && A[j+i].last == A[i].last && A[j+i].first == A[i].first) 
        { 
         if (A[j+i].score >= A[i].score) 
          max = A[j+i]; 
         j++; 
        } 
        j--; 
   
        if (max.score >= 0) 
         cout << max.last << " " << max.first << " " << max.score << endl; 
       } 
       cout << endl; 
   
       return 0; 
   } 
   
   bool before(playerscore a, playerscore b) 
   { 
        return a.score > b.score; 
   } 
   
   void selectionsort(playerscore *A, int n) 
   { 
       for(int length = n; length > 1; length--) 
       { 
        //find imax, index of largest 
        int imax = 0, i; 
        for(i = 1; i < length; i++) 
         if(before(A[imax], A[i])) 
          imax = i; 
        // swap A[imax] and the last element 
        playerscore temp = A[imax]; 
        A[imax] = A[length-1]; 
        A[length-1] = temp; 
       } 
   } 
   

Answer 2

1. 排序以升序對數組的名字。 如果比較的名稱相同，則得分較高的元素應該到達數組的較早位置。
2. 打印名稱與前一個元素不同的第一個元素和元素。

樣品實施：

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

struct playerscore 
{ 
    string first, last; 
    int score; 
}; 

bool score(playerscore a, playerscore b); 
void selectionsort(playerscore *A, int n); 

int main() 
{ 
    string file; 
    int n; 
#if 0 
    cin >> file; 
    ifstream fin(file.c_str()); 
#else 
#define fin cin // to test with online compiler 
#endif 
    fin >> n; 

    // read in the names and the scores in the form of struct playerscore 
    playerscore *A = new playerscore[n]; 
    for(int i = 0; i < n; i++) 
     fin >> A[i].first >> A[i].last >> A[i].score; 

    // sort the data 
    selectionsort(A, n); 

    // print in sorted order 
    for(int i = 0; i < n; i++) 
     if (i == 0 || A[i].first != A[i - 1].first || A[i].last != A[i - 1].last) 
      cout << A[i].first << " " << A[i].last << " " << A[i].score << "\n"; 
    cout << endl; 

    return 0; 
} 

bool before(playerscore a, playerscore b) 
{ 
    return a.first == b.first ? (a.last == b.last ? a.score > b.score : a.last < b.last) : a.first < b.first; 
} 
void selectionsort(playerscore *A, int n) 
{ 
    for(int length = n; length > 1; length--) 
    { 
     //find imax, index of largest 
     int imax = 0, i; 
     for(i = 1; i < length; i++) 
      if(before(A[imax], A[i])) 
       imax = i; 
     // swap A[imax] and the last element 
     playerscore temp = A[imax]; 
     A[imax] = A[length-1]; 
     A[length-1] = temp; 
    } 
} 

Answer 3

你已經做了困難的部分。

假設((first, last), score)對已經排序，每個球員得分最高的是這位玩家的第一個記錄，所以只要保持目前的球員的名字作爲curr_name當您訪問數組：

1. 如果下一個名稱與curr_name相同，您可以放心地忽略此項目。
2. 如果不是，請打印此記錄並更新curr_name。

的代碼是一樣自爆：

#include <iostream> 
#include <fstream> 
#include <algorithm> 
#include <vector> 
#include <string> 
#include <utility> 
using namespace std; 
bool mycmp (pair<pair<string, string>, int> a, pair<pair<string, string>, int> b) { 
    return a.first < b.first || (a.first == b.first && a.second > b.second); 
} 
int main(int argc, char *argv[]) 
{ 
    ifstream fin("data.txt"); 
    int n; 
    fin>>n; 
    vector<pair<pair<string, string>, int>> A(n); 
    for(int i = 0; i < n; ++i){ 
     fin>>A[i].first.first>>A[i].first.second>>A[i].second; 
    } 
    sort(A.begin(), A.end(), mycmp); 
    pair<string, string> cur_name; 
    for(int i = 0; i < n; ++i){ 
     if(cur_name != A[i].first){ 
      cout<<A[i].first.first<<" "<<A[i].first.second<<" "<<A[i].second<<endl; 
      cur_name = A[i].first; 
     } 
    } 
    return 0; 
}