PAT甲級 1084

題目 Broken Keyboard

On a broken keyboard, some of the keys are worn out. So when you type some sentences, the characters corresponding to those keys will not appear on screen.
Now given a string that you are supposed to type, and the string that you actually type out, please list those keys which are for sure worn out.
Input Specification:
Each input file contains one test case. For each case, the 1st line contains the original string, and the 2nd line contains the typed-out string. Each string contains no more than 80 characters which are either English letters [A-Z] (case insensitive), digital numbers [0-9], or _ (representing the space). It is guaranteed that both strings are non-empty.
Output Specification:
For each test case, print in one line the keys that are worn out, in the order of being detected. The English letters must be capitalized. Each worn out key must be printed once only. It is guaranteed that there is at least one worn out key.

解析

判斷第一個字符中有哪些字符是第二個字符串中沒有的，輸出該字符的大寫

代碼

#include<bits/stdc++.h>

#define INF 1<<29

using namespace std;


void pat1084() {
    string origin_str, type_str,temp;
    cin >> origin_str >> type_str;
    transform(origin_str.begin(), origin_str.end(), origin_str.begin(), ::toupper);
    transform(type_str.begin(), type_str.end(), type_str.begin(), ::toupper);
    for (char i : origin_str) {
        bool flag = false;
        for (char j : type_str) {
            if (i == j) {
                flag = true;
                break;
            }
        }
        if(!flag&& temp.find(i) == -1){
            temp += i;
            cout<<i;
        }
    }
}


int main() {
    pat1084();
    return 0;
}