Codeforces 484C Strange Sorting (replacement)

Codeforces 484C Strange Sorting (replacement)

Link: Codeforces 484C Strange Sorting

Given a string with a length of N, there are now M queries, each time from left to right, perform D-sorting on the substring with a length of K one by one, and finally

Output the generated string.

Solution: the problem is a replacement idea. The replacement of L is shifted to the first place, and C corresponds to the replacement of K before D-sorting.

Execute L to ensure that D-sorting is a different K-length substring. Solve the string using the idea similar to the Rapid power of the matrix, and finally migrate it cyclically.

The corresponding N-K bit.

#include 
  
   #include 
   
    #include using namespace std;const int maxn = 1e6+5;int N, M, K, D, L[maxn];int C[maxn], P[maxn], x[maxn], tmp[maxn];char str[maxn];void multi () {    for (int i = 0; i < N; i++) tmp[i] = x[x[i]];    for (int i = 0; i < N; i++) x[i] = tmp[i];}int main () {    scanf("%s%d", str, &M);    N = strlen(str);    for (int i = 0; i < N; i++)        L[i] = (i ? i - 1 : N - 1);    while (M--) {        scanf("%d%d", &K, &D);        for (int i = 0; i < N; i++) C[i] = i;        int mv = 0;        for (int i = 0; i < D; i++) {            for (int j = i; j < K; j += D)                C[j] = mv++;        }        for (int i = 0; i < N; i++) P[i] = C[i];        for (int i = 0; i < N; i++) x[i] = C[L[i]];        int n = N - K;        while (n) {            if (n&1) {                for (int i = 0; i < N; i++)                    P[i] = x[P[i]];            }            multi();            n >>= 1;        }        for (int i = 0; i < N; i++) tmp[P[i]] = str[i];        for (int i = 0; i < N; i++) str[(i + (N - K)) % N] = tmp[i];        printf("%s\n", str);    }    return 0;}