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解

跟有点像。

代码

#include 
   
    #include 
    
     #include 
     
      #include 
      
       using namespace std;string a, b;int j, n, l, k, kmp[1000010], f[1000010];long long ans;void work() {       kmp[0] = kmp[1] = j = 0;    n = a.size() - 1;    for (int i = 2; i <= n; ++i) {           while (a[i] != a[j + 1] && j) j = kmp[j];        if (a[i] == a[j + 1])            ++j;        kmp[i] = j;        l = j;        while (l >= k) {               if (l * 2 + 1 <= i) {                   ++ans;                break;            }            l = kmp[l];        }    }    a.erase(1, 1);  //删位}int main() {       cin >> a;    cin >> k;    a = " " + a;    while (a.size() > 2 * k + 1) work();    printf("%d", ans);}