33 lines
813 B
C++
33 lines
813 B
C++
// lanqiao3514 字串简写(枚举)
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#include<bits/stdc++.h>
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using namespace std;
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#define int long long
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signed main(){
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int k;
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string s;
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char a, b;
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cin >> k >> s >> a >> b;
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vector<int> ft, bk;
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for(int i = 0; i < s.size(); i++){
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if(a == s[i]) ft.push_back(i);
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}
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for(int i = 0; i < s.size(); i++){
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if(b == s[i]) bk.push_back(i);
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}
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int ans = 0;
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for(int i = 0; i < ft.size(); i++){
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for(int j = 0; j < bk.size(); j++){
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if( bk[j] - ft[i] + 1 < k) continue;
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else{
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ans += bk.size() - j; // 1 2 1 1 1
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break; // 找到一个符合条件的，直接把后面全加上，然后跳出此次循环
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}
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}
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}
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cout << ans << endl;
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return 0;
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}
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/* samples -> 6
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4
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abababdb a b
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*/ |