C. Alphabetic Removals
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output
You are given a string ss consisting of nn lowercase Latin letters. Polycarp wants to remove exactly kk characters (k≤nk≤n) from the string ss. Polycarp uses the following algorithm kk times:
- if there is at least one letter 'a', remove the leftmost occurrence and stop the algorithm, otherwise go to next item;
- if there is at least one letter 'b', remove the leftmost occurrence and stop the algorithm, otherwise go to next item;
- ...
- remove the leftmost occurrence of the letter 'z' and stop the algorithm.
This algorithm removes a single letter from the string. Polycarp performs this algorithm exactly kk times, thus removing exactly kk characters.
Help Polycarp find the resulting string.
Input
The first line of input contains two integers nn and kk (1≤k≤n≤4⋅1051≤k≤n≤4⋅105) — the length of the string and the number of letters Polycarp will remove.
The second line contains the string ss consisting of nn lowercase Latin letters.
Output
Print the string that will be obtained from ss after Polycarp removes exactly kk letters using the above algorithm kk times.
If the resulting string is empty, print nothing. It is allowed to print nothing or an empty line (line break).
Examples
input
Copy
15 3
cccaabababaccbc
output
Copy
cccbbabaccbc
input
Copy
15 9
cccaabababaccbc
output
Copy
cccccc
input
Copy
1 1
u
output
Copy
挨个去除26字母即可,两重循环
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cctype>
#include<cmath>
#include<iostream>
#include<sstream>
#include<iterator>
#include<algorithm>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<stack>
#include<deque>
#include<queue>
#include<list>
using namespace std;
const double eps = 1e-8;
typedef long long LL;
typedef unsigned long long ULL;
const int INF = 0x3f3f3f3f;
const int INT_M_INF = 0x7f7f7f7f;
const LL LL_INF = 0x3f3f3f3f3f3f3f3f;
const LL LL_M_INF = 0x7f7f7f7f7f7f7f7f;
const int dr[] = {0, 0, -1, 1, -1, -1, 1, 1};
const int dc[] = {-1, 1, 0, 0, -1, 1, -1, 1};
const int MOD = 1e9 + 7;
const double pi = acos(-1.0);
const int MAXN=40010;
const int MAXM=100010;
const int M=110;
int n;
int main()
{
int n,m;
while(scanf("%d",&n)!=EOF)
{
char s[105];
cin>>s;
for(int i=1;i<=n;i++)
{
if(n%i==0)
reverse(s,s+i);
}
cout<<s<<endl;
}
return 0;
}