#include<bits/stdc++.h> #define se second #define fi first using namespace std; const int nmax = 200002; int N,K,R; int arr[nmax]; int syar[nmax]; int hit[nmax]={0}; int main() { cin >> N >> K >> R; for(int i=1; i<=N; i++) { cin >> arr[i]; hit[arr[i]]++; } bool impo=false; int inp, freq; for(int i=1; i<=R; i++) { cin >> inp >> freq; syar[inp] = freq; if(hit[inp]<freq) impo=true; } if(impo) { cout << "impossible" << endl; return 0; } memset(hit,0,sizeof(hit)); int res=INT_MAX; int idx = 0; int uj1 = 1; int terms = R; while (idx<=N) { if(terms >= 1) { idx++; hit[arr[idx]]++; if(hit[arr[idx]]==syar[arr[idx]]) terms--; } else { res = min(res, idx-uj1+1); if(hit[arr[uj1]]==syar[arr[uj1]]) terms=1; hit[arr[uj1]]--; uj1++; } } cout << res << endl; return 0; }