Codeforces Round #402 (Div. 2)

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;inline int read(){    char c=getchar();int x=0,f=1;    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1; c=getchar();}    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘; c=getchar();}    return x*f;}int n,a[10],b[10],ans;int main(){    //freopen("in","r",stdin);    n=read();    for(int i=1;i<=n;i++) a[read()]++;    for(int i=1;i<=n;i++) b[read()]++;    for(int i=1;i<=5;i++){        int c=a[i]+b[i];        if(c&1) {puts("-1");return 0;}        else ans+=abs(c/2-a[i]);    }    printf("%d",ans/2);}

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;inline int read(){    char c=getchar();int x=0,f=1;    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1; c=getchar();}    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘; c=getchar();}    return x*f;}char s[20];int n,k;int main(){    //freopen("in","r",stdin);    scanf("%s",s+1);k=read();    n=strlen(s+1);    int c=0;    for(int i=1;i<=n;i++) if(s[i]==‘0‘) c++;    if(c<k) printf("%d",n-1);    else{        int now=0,zero=0;        for(int i=n;i>=1;i--){            if(s[i]==‘0‘) zero++;            else now++;            if(zero==k) break;        }        printf("%d",now);    }}

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;const int N=2e5+5;inline int read(){    char c=getchar();int x=0,f=1;    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1; c=getchar();}    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘; c=getchar();}    return x*f;}int n,k,ans;struct Item{    int a,b,c;    bool operator <(const Item &r)const{        return c>r.c;    }}a[N];int main(){    //freopen("in","r",stdin);    n=read();k=read();    for(int i=1;i<=n;i++) a[i].a=read();    for(int i=1;i<=n;i++) a[i].b=read();    for(int i=1;i<=n;i++) a[i].c=a[i].b-a[i].a;    sort(a+1,a+1+n);    int i;    for(i=1;i<=k;i++) ans+=a[i].a;    while(i<=n&&a[i].c>=0) ans+=a[i].a,i++;    for(;i<=n;i++) ans+=a[i].b;    printf("%d",ans);}

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;const int N=2e5+5;inline int read(){    char c=getchar();int x=0,f=1;    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1; c=getchar();}    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘; c=getchar();}    return x*f;}int n,t[N],m;char a[N],b[N];bool check(int g){    int now=1;    for(int i=1;i<=n;i++) if(t[i]<=g){        if(a[i]==b[now]) now++;        if(now>m) return true;    }    return false;}void solve(){    int l=1,r=n,ans=0;    while(l<=r){        int mid=(l+r)>>1;        if(check(mid)) ans=mid,r=mid-1;        else l=mid+1;    }    printf("%d",n-ans);}int main(){    //freopen("in","r",stdin);    scanf("%s%s",a+1,b+1);    n=strlen(a+1);    m=strlen(b+1);    for(int i=1;i<=n;i++) t[read()]=n-i+1;    solve();}