第3周 字符串 作业题

1.cpp

#include <iostream>
using namespace std;



void getResult(char str[]){

    int numbers[26];
    for(int j = 0; j < 26; j ++)
        numbers[j] = 0;

    int i = 0;

    while(str[i] != '\0'){
        numbers[str[i] - 'a'] ++;
        i ++;
    }

    i = 0;
    char maxChar = 0;
    int max = numbers[0];

    for(int j = 1; j < 26; j ++){
        if(max < numbers[j]){
            max = numbers[j];
            maxChar = j;
        }
    }

    maxChar = maxChar + 'a';

    cout <<maxChar<<" "<<max<<endl;

}



int main(){


    int cases;
    cin >> cases;

    for(int i = 0; i < cases - 1; i ++){
        char str[1001];
        cin >> str;
        getResult(str);
    }

    char str[1001];
    cin >> str;
    getResult(str);


    return 0;
}

2.cpp

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>

using namespace std;
const char END_STR[] = "ENDOFINPUT";

int main()
{
    char str[20],chs[300];

    while(gets(str),strcmp(str,END_STR) != 0)
    {
        gets(chs);
        int length = strlen(chs);

        for(int i = 0; i < length; i++)
        {
            if(chs[i] >= 'A' && chs[i] <= 'Z')    cout<<(char)((chs[i]-'A'-5+26)%26 + 'A');
            else cout<<chs[i];
        }

        cout<<endl;
        gets(str);
    }


    return 0;
}

3.cpp

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

void check(string s1, string s2){
    if (s1.length() != s2.length()){
        cout << "NO" <<endl;
        return;
    }

    int before[26] = {0};
    int after[26] = {0};

    for(int i= 0; i < s1.length(); i ++){
        before[s1.at(i) - 'A'] ++;
        after[s2.at(i) - 'A'] ++;
    }

    sort(before, before + 26);
    sort(after, after + 26);

    for(int i = 0; i < 26; i ++){
        if (before[i] != after[i]){
            cout << "NO" <<endl;
            return;
        }
    }

    cout << "YES" <<endl;


}

int main(){


    string s1, s2;
    getline(cin, s1);
    getline(cin, s2);

    check(s1, s2);

    return 0;
}

4.cpp

#include <iostream>

using namespace std;

char input[1000001];
int prefixArray[1000001];


int* prefixFunction(char str[], int size){

    prefixArray[0] = -1;

    int k = -1;
    for(int i = 1; i < size ; i ++){

        while(k > -1 && str[k+1] != str[i])
            k = prefixArray[k];

        if(str[i] == str[k+1])
            k ++;

        prefixArray[i] = k;
    }

}

int main(){

    int number;
    int index = 0;

    while(1){

        cin >> number;
        if (number == 0) break;

        index ++;
        cin >> input;




        prefixFunction(input, number);
        cout <<"Test case #" <<index<<endl;



        for(int i = 1; i <number; i ++){
            int preriodLenght = i - *(prefixArray+i);
            if((i+1) % preriodLenght == 0){
                int many = (i+1) / preriodLenght;
                if(many >= 2)
                    cout << i + 1 <<" " <<many<<endl;

            }
        }

        cout << endl;
    }

    return 0;
}