第十六次CCF计算机软件能力认证题解

我在场外，只做了第二题和第三题。就说说这两道题目吧。

这道题目，就是给你一个只包含七个字符的式子，判断是否等于24。按照四则混合运算进行计算。所以需要先做乘法和除法。再做加法和减法。

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <map>
#include <set>
#include <stack>
#include <queue>
using namespace std;
int a[4];
char b[3];
int getTag(string s);

int main() {
    int n;
    scanf("%d",&n);
    for(int i=0;i<n;i++){
    	string s;
    	cin>>s;
		int ans = getTag(s);
		printf("%s\n",(ans==24)?"Yes":"No"); 	
	}
}

int getTag(string s){
	int n = s.length();
	a[0] = s[0] - '0';
	int cnt = 1; 
	int cntb = 0;
	for(int i=1;i<n;i++){
		if(i%2==0){
			a[cnt++] = s[i] - '0';
		}else{
			b[cntb++] = s[i];
		}
	} 
	int tmp;
	for(int i=0;i<3;i++){
		if(b[i]=='+' || b[i]=='-'){
			continue;
		}else{
			if(b[i]=='x'){
				int l = i;
				while(a[l]==-1){
					l = l - 1;
				}
				tmp = a[l] * a[i+1];
				a[l] = tmp;
				a[i+1] = -1;
			}else if(b[i]=='/'){
				int l = i;
				while(a[l]==-1){
					l = l - 1;
				}
				tmp = a[l] / a[i+1];
				a[l] = tmp;
				a[i+1] = -1;
			}
		}
	}
	int ans = a[0];
	for(int i=0;i<3;i++){
		if(b[i]=='+'){
			ans = ans + (a[i+1]);
		}else if(b[i]=='-'){
			ans = ans - (a[i+1]);
		}
	}
	return ans;
}

第三题


这道题是一个大模拟，题目可以仔细看看

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <cmath>
using namespace std;
const int maxn = 1100;
int n,s,l;
struct node{
    int number;
    string value;
};
set<int> numbers;
node a[maxn];
int xx[1000000];
int yy[1000000];
int getPanHao(int tiao_dai_bian_hao){
    return xx[tiao_dai_bian_hao];
}

int getPaiHao(int tiao_dai_bian_hao){
    return yy[tiao_dai_bian_hao];
}

int getPaiNeiPaiHao(int tiaodaibianhao, int b){
    int hah = b - tiaodaibianhao * s;
    return hah;
}

int getBegin(int tiao_dai_bian_hao, int b){
    int hah = b - tiao_dai_bian_hao * s;
    int paihao = getPaiHao(tiao_dai_bian_hao);
    int total = paihao * s + hah;
    return total*8;
}

int getten(char cc){
    int nnnn = cc - '0';
    if (nnnn>=0 && nnnn<=9){
        return nnnn;
    } else{
        return cc - 'A' + 10;
    }
}

char get16(int dd){
    if (dd<10){
        return dd+'0';
    } else{
        int xxx = dd - 10;
        xxx = xxx + 'A';
        return xxx;
    }
}

char yihuo(char aa,char bb){
    int ans = getten(aa) ^ getten(bb);
    return get16(ans);
}
int main(){
    scanf("%d%d%d",&n,&s,&l);
    int max_bian_hao = -1;
    for(int i=0;i<l;i++){
        cin>>a[i].number>>a[i].value;
        numbers.insert(a[i].number);
        if(i==0){
            int tmp = a[i].value.length();
            tmp = tmp / 8;
            tmp = tmp / s;
            max_bian_hao = tmp * (n-1);
        }
    }
    // < n
    int x = 0;
    int y = 0;

    for(int i=0;i<max_bian_hao;i++){
        xx[i] = x;
        yy[i] = y;
        x = x + 1;
        if (x >= n ){
            x = 0;
            if(((x+y)-(n-1))%n == 0){
                y = y+1;
                continue;
            }
        }
        int kk = x+y;
        if( (kk-(n-1))%n == 0 ){
        	x = x - 1;
            x = x+1;
            y = y+1;
        }
    }
    int m;
    scanf("%d",&m);
    for(int i = 0;i<m;i++){
        int b ;
        scanf("%d",&b);
        if((n-l)>1){
            printf("-\n");
            continue;
        }
        int tiao_dai_bian_hao = floor(b/s);
        if(tiao_dai_bian_hao > max_bian_hao){
            printf("-\n");
            continue;
        }
        int panhao = getPanHao(tiao_dai_bian_hao);
        if(numbers.count(panhao)==1){
        	
            int begin = getBegin(tiao_dai_bian_hao,b);
            string ans = "";
            for(int j=0;j<l;j++){
                if(a[j].number == panhao){
                	int rr = begin + 8;
                	int ll = begin;
                    ans = a[j].value.substr(ll,8);
                    cout<<ans<<endl;
                    break;
                }
            }
        }else{
            // 需要找到其他的进行异或
            int begin = getBegin(tiao_dai_bian_hao,b);
            int ans[8];
            string anstrue[8];
            for(int k=0;k<8;k++){
                ans[k] = 0;
                for (int j = 0; j < l; ++j) {
                    ans[k] = ans[k] ^ getten(a[j].value[begin+k]);
//                    printf("%d\n",getten(a[j].value[begin+k]));
                }
                char hahah = get16(ans[k]);
            	printf("%c",hahah);
			}
            printf("\n");
        }
    }
    return 0;
}