#include <bits/stdc++.h> using namespace std; #define mp make_pair #define pb push_back typedef long long int LLI; typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pii> vpii; char S[200000]; int pre[3][200001],n[3][200001]; int main() { int i,j; int N,K; scanf("%d %d",&N,&K); for (i = 0; i < N; i++) { scanf(" %c",&S[i]); for (j = 0; j < 3; j++) pre[j][i+1] = pre[j][i]; if (S[i] == 'J') pre[0][i+1]++; else if (S[i] == 'O') pre[1][i+1]++; else pre[2][i+1]++; } int ans = 1e9; j = 0; for (i = 0; i < N; i++) { while (pre[0][i+1]-pre[0][j] >= K) j++; n[0][i] = j-1; } j = 0; for (i = 0; i < N; i++) { while (pre[1][i+1]-pre[1][j] >= K) j++; n[1][i] = j-1; } j = 0; for (i = 0; i < N; i++) { while (pre[2][i+1]-pre[2][j] >= K) j++; n[2][i] = j-1; } for (i = 0; i < N; i++) { int u = n[2][i]-1; if (u >= 0) u = n[1][u]-1; else u = -2; if (u >= 0) u = n[0][u]-1; else u = -2; if (u != -2) ans = min(ans,i-u); } if (ans == 1e9) printf("-1\n"); else printf("%d\n",ans-3*K); return 0; }

ho_t2.cpp: In function 'int main()':
ho_t2.cpp:15:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&N,&K);
     ~~~~~^~~~~~~~~~~~~~~
ho_t2.cpp:17:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf(" %c",&S[i]);
         ~~~~~^~~~~~~~~~~~~