csp模拟题-201903

#include<iostream> 
#include<cstdio>
#define maxn 100010
using namespace std;
int a[maxn],n;
int main(){
    scanf("%d",&n);
    for(int i=1;i<=n;i++)scanf("%d",&a[i]);
    int x,z;
    double y;
    x=a[1];z=a[n];
    if(x<z)swap(x,z);
    printf("%d ",x);
    if(n%2==0){
        y=(double)(a[n/2]+a[n/2+1])/2.0;
    }
    else {
        y=a[n/2+1];
    }
    if(y==(int)y)printf("%.0f ",y);
    else printf("%.1f ",y);
    printf("%d\n",z);
    return 0;
    
}

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
int n,st[10],top;
char s[10];
int main(){
    freopen("Cola.txt","r",stdin);
    scanf("%d",&n);
    while(n--){
        top=0;
        scanf("%s",s+1);
        int pre=1; 
        for(int i=1;i<=7;i++){
            if(s[i]<=‘9‘&&s[i]>=‘1‘){
                int a=s[i]-‘0‘;
                st[++top]=pre*a;
            }
            else{
                if(s[i]==‘+‘)pre=1;
                else if(s[i]==‘-‘)pre=-1;
                else if(s[i]==‘x‘){
                    int b=s[i+1]-‘0‘;
                    int a=st[top];
                    st[top]=a*b;
                    i++;
                }
                else{
                    int b=s[i+1]-‘0‘;
                    int a=st[top];
                    st[top]=a/b;
                    i++;
                }
            }
        }
        int ans=0;
        for(int i=1;i<=top;i++)ans+=st[i];
//        printf("%d\n",ans); 
        if(ans==24){puts("Yes");}
        else {puts("No");}
    }
    return 0;
}