#include<bits/stdc++.h> using namespace std; #define foru(i,a,b) for(int i=(a); i<=(b); ++i) #define ford(i,a,b) for(int i=(a); i>=(b); --i) #define rep(i,a) for(int i=0; i<(a); ++i) #define sz(a) (int)(a).size() #define all(a) (a).begin(),(a).end() #define bit(s,i) (((s)>>(i))&1) #define ii pair<int,int> #define vi vector<int> #define vii vector<ii> #define fi first #define se second #define ll long long #define eb emplace_back #define pb push_back #define __builtin_popcount __builtin_popcountll #define _ << " " << template <class X, class Y> bool maxi(X &x, Y y){return x<y?x=y,true:false;} template <class X, class Y> bool mini(X &x, Y y){return x>y?x=y,true:false;} const int N=1e6+5; int n,dp[N][3][2]; string A,B; void solve(){ cin>>n>>A>>B; memset(dp,0x3f,sizeof(dp)); dp[0][0][0]=0; foru(i,0,n-1){ foru(as,1,2) rep(tog,2){ mini(dp[i][as][tog], dp[i][0][tog]+1); } rep(as,3){ mini(dp[i][as][1], dp[i][as][0]+1); } rep(as,3) rep(tog,2){ mini(dp[i][0][tog],dp[i][as][tog]); mini(dp[i][as][0], dp[i][as][tog]); } rep(as,3) rep(tog,2){ int st=A[i]-'0'; if(as>0) st=as-1; if(tog==1) st^=1; if(st==B[i]-'0') mini(dp[i+1][as][tog],dp[i][as][tog]); } } int res=1e9; rep(as,3) rep(tog,2) mini(res,dp[n][as][tog]); cout<<res<<'\n'; } int32_t main(){ #define task "test" if(fopen(task".inp", "r")){ freopen(task".inp", "r", stdin); freopen(task".out", "w", stdout); } cin.tie(0)->sync_with_stdio(0); int tc=1; //cin>>tc; foru(i,1,tc){ solve(); } }

lamp.cpp: In function 'int32_t main()':
lamp.cpp:63:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
lamp.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~