STL – Page 2 – hahaschool

Codeforces 501 B Misha and Changing Handles

January 17, 20152015-01-17hahaschoolLeave a comment

#include <iostream>
#include <algorithm>
#include <queue>
#include <vector>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <ctime>
#include <iomanip>
#include <cmath>
#include <set>
#include <map>

using namespace std;

int main(){
    map<string, string> id;

    int num = 0;
    cin >> num;
    while (num--) {
        string oldid,newid;
        cin >> oldid >> newid;
        bool flag = false;
        map<string,string>::iterator it;
        for (it = id.begin(); it != id.end(); it++) {
            if ((*it).second == oldid) {
                flag = true;
                (*it).second = newid;
                break;
            }
        }
        if (!flag) {
            id[oldid] = newid;
        }
    }
    cout << id.size() << endl;
    map<string,string>::iterator it;
    for (it = id.begin(); it != id.end(); it++) {
        cout << (*it).first << ' ' << (*it).second << endl;
    }


    return 0;
}

#include <iostream>

#include <algorithm>

#include <queue>

#include <vector>

#include <cstdlib>

#include <cstdio>

#include <string>

#include <cstring>

#include <ctime>

#include <iomanip>

#include <cmath>

#include <set>

#include <map>

using namespace std;

int main(){

map<string, string> id;

int num = 0;

cin >> num;

while (num--) {

string oldid,newid;

cin >> oldid >> newid;

bool flag = false;

map<string,string>::iterator it;

for (it = id.begin(); it != id.end(); it++) {

if ((*it).second == oldid) {

flag = true;

(*it).second = newid;

break;

}

if (!flag) {

id[oldid] = newid;

}

cout << id.size() << endl;

map<string,string>::iterator it;

for (it = id.begin(); it != id.end(); it++) {

cout << (*it).first << ' ' << (*it).second << endl;

}

return 0;

}

STL小练习系列

POJ 1256 Anagram

January 17, 20152015-01-17hahaschoolLeave a comment

#include <iostream>
#include <algorithm>
#include <queue>
#include <vector>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <ctime>
#include <iomanip>
#include <cmath>
#include <set>
#include <map>

using namespace std;


char chain[52] = {'A','a','B','b','C','c','D','d','E','e','F','f','G','g','H','h','I','i','J','j','K','k','L','l','M','m','N','n','O','o','P','p','Q','q','R','r','S','s','T','t','U','u','V','v','W','w','X','x','Y','y','Z','z'};
bool cmp(char a,char b){
    if (a == b) {
        return false;
    }
    bool flag = false;
    for (int i = 0;i < 52;i++) {
        if (a == chain[i]) {
            flag = true;
            break;
        }
        if (b == chain[i]) {
            flag = false;
            break;
        }
    }
    return flag;
}

int main(){
    int cnt;
    cin >> cnt;
    while (cnt--) {
        string toProc;
        cin >> toProc;
        while (next_permutation(toProc.begin(), toProc.end(),cmp)) {

        }
        cout << toProc << endl;
        while (next_permutation(toProc.begin(), toProc.end(),cmp)) {
            cout << toProc << endl;
        }


    }

    return 0;
}

#include <iostream>

#include <algorithm>

#include <queue>

#include <vector>

#include <cstdlib>

#include <cstdio>

#include <string>

#include <cstring>

#include <ctime>

#include <iomanip>

#include <cmath>

#include <set>

#include <map>

using namespace std;

char chain[52] = {'A','a','B','b','C','c','D','d','E','e','F','f','G','g','H','h','I','i','J','j','K','k','L','l','M','m','N','n','O','o','P','p','Q','q','R','r','S','s','T','t','U','u','V','v','W','w','X','x','Y','y','Z','z'};

bool cmp(char a,char b){

if (a == b) {

return false;

}

bool flag = false;

for (int i = 0;i < 52;i++) {

if (a == chain[i]) {

flag = true;

break;

}

if (b == chain[i]) {

flag = false;

break;

}

return flag;

}

int main(){

int cnt;

cin >> cnt;

while (cnt--) {

string toProc;

cin >> toProc;

while (next_permutation(toProc.begin(), toProc.end(),cmp)) {

}

cout << toProc << endl;

while (next_permutation(toProc.begin(), toProc.end(),cmp)) {

cout << toProc << endl;

}

return 0;

}

next_permutation的返回bool值的含义是接下来还有没有可以用的排列。

然后要注意这个题的排序方式是特殊的，要自己构建排序函数。

排序函数返回值的意思是：如果返回true，则交换两个值，返回false，则不对两个值操作，所以如果a＝＝b一定要返回false，否则会死循环。

UVA 10420 List of Conquests

January 17, 20152015-01-17hahaschoolLeave a comment

#include <iostream>
#include <algorithm>
#include <queue>
#include <vector>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <ctime>
#include <iomanip>
#include <cmath>
#include <set>
#include <map>

using namespace std;

int main(){
    int cnt;
    cin >> cnt;
    map<string, set<string> > container;
    while (cnt--) {
        string country;
        cin >> country;
        string name;
        getchar();
        getline(cin, name);
        container[country].insert(name);
    }
    map<string, set<string> >::iterator it;
    for (it = container.begin(); it != container.end(); it++) {
        cout << (*it).first << ' ' << (*it).second.size() << endl;
    }


    return 0;
}

#include <iostream>

#include <algorithm>

#include <queue>

#include <vector>

#include <cstdlib>

#include <cstdio>

#include <string>

#include <cstring>

#include <ctime>

#include <iomanip>

#include <cmath>

#include <set>

#include <map>

using namespace std;

int main(){

int cnt;

cin >> cnt;

map<string, set<string> > container;

while (cnt--) {

string country;

cin >> country;

string name;

getchar();

getline(cin, name);

container[country].insert(name);

}

map<string, set<string> >::iterator it;

for (it = container.begin(); it != container.end(); it++) {

cout << (*it).first << ' ' << (*it).second.size() << endl;

}

return 0;

}

STL的使用小练习