比赛链接:https://codeforc.es/contest/1385
pro:3.5 / 7
=====A=====
*题意:多组数据,每组三个正整数$x, y, z$,构造$a, b, c$满足$x = max(a, b)$, $y = max(a, c)$, $z= max(b, c)$
*题解:签到题,分类特判即可
#include
using namespace std;
typedef long long ll;
const int maxn = 2e5 + 5;
const double pi = acos(-1);
const int mod = 998244353;
int x, y, z, a, b, c;
int t;
int main(){
cin >> t;
while(t--){
cin >> x >> y >> z;
int a = (x == y) + (x == z) + (y == z);
if(!a){
puts("NO");
continue;
}
else if(a == 3){
puts("YES");
cout << x << ' ' << x << ' ' << x << endl;
continue;
}
else{
if((x == y && z > x) || (x == z && y > x) || (y == z && x > y)) puts("NO");
else{
puts("YES");
if(x == y) cout << x << ' ' << z << ' ' << z << endl;
else if(x == z) cout << x << ' ' << y << ' ' << y << endl;
else cout << y << ' ' << x << ' ' << x << endl;
}
}
}
}
=====B=====
*题意:给定多组有且仅有两次重复的数字序列,在不影响相对顺序的前提下去重
*题解:签到题,打标记跳输出即可
#include
using namespace std;
typedef long long ll;
const int maxn = 2e5 + 5;
const double pi = acos(-1);
const int mod = 998244353;
int t;
int n;
int a[105];
int main(){
cin >> t;
while(t--){
cin >> n;
int tmp;
memset(a, 0, sizeof(a));
for(int i = 1; i <= 2 * n; ++i){
cin >> tmp;
if(a[tmp]) continue;
cout << tmp << ' ';
a[tmp] = 1;
}
puts("");
}
}
=====C=====
*题意:定义“good”序列:每次从首位或末位拿出元素,组成的新序列单调不降。多组数据,给定序列,询问删去从首位开始的至少多少元素,可以使序列成为“good”序列?
*题解:所谓“good”序列就是从首末开始到某一位置都单调不降的序列,只需倒序遍历,先找不降序列,由此后找不升序列,统计剩余元素个数输出即可
#include
using namespace std;
typedef long long ll;
const int maxn = 2e5 + 5;
const double pi = acos(-1);
const int mod = 998244353;
int t;
int n;
int a[maxn];
int main(){
cin >> t;
while(t--){
cin >> n;
for(int i = 1; i <= n; ++i) cin >> a[i];
if(n == 1){
cout << 0 << endl;
continue;
}
int p = -1, q = -1;
for(int i = n; i > 1; --i){
if(a[i-1] < a[i]){
p = i;
break;
}
}
if(p == -1){
cout << 0 << endl;
continue;
}
for(int i = p; i > 1; --i){
if(a[i-1] > a[i]){
q = i;
break;
}
}
if(q == -1) cout << 0 << endl;
else cout << q - 1 << endl;
}
}
=====D=====
*见本周推荐