Submission #1228929

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Source Code Expand

#include<bits/stdc++.h>
#define rep(i,k,n) for(int i=k;i<=n;i++)
#define rep2(i,k,n) for(int i=k;i>=n;i--)
#define pb push_back
using namespace std;
const int N=1e6+7;
vector<int> tu[26];
char S[N],T[N];
int n,R[N],ans;
int main(){
	scanf("%d%s%s",&n,S+1,T+1);
	rep(i,0,25)tu[i].pb(0);
	rep(i,1,n)R[i]=i,tu[S[i]-'a'].pb(i);
	int now=n;
	rep2(i,n,1){
		now=min(now,i);
		int op=T[i]-'a',pos=*(--upper_bound(tu[op].begin(),tu[op].end(),now));
		if(!pos){puts("-1");return 0;}
		R[pos]=max(R[pos],i);
		now=pos;
	}
	int res;now=0;
	rep(i,1,n)if(R[i]!=i){
		if(i>now)res=0;
		res++,ans=max(ans,res),now=R[i];
	}
	printf("%d\n",ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:11:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%s%s",&n,S+1,T+1);
                            ^

Judge Result