C - いっしょ / Be Together

枚举即可。

#include
     
      #include
      
       using namespace std;int n, a[111], ans = ~0U >> 1;inline int sqr(int x) {    return x * x;}inline int calc(int x) {    int res = 0;    for (int i = 1; i <= n; ++i)        res += sqr(a[i] - x);    return res;}int main() {    cin >> n;    for (int i = 1; i <= n; ++i) cin >> a[i];    for (int i = -100; i <= 100; ++i)        ans = min(ans, calc(i));    cout << ans << endl;    return 0;}
      
     

D - アンバランス / Unbalanced

扫一遍即可。

#include
     
      #include
      
       #include
       
        #include
        
         #include
         
          using namespace std;char a[100005];int main() {    scanf("%s", a + 1);    int n = strlen(a + 1), l = -1, r = -1;    for (int i = 1; i <= n; ++i) {        if (i + 1 <= n && a[i] == a[i+1]) {            l = i; r = i + 1; break;        }        if (i + 2 <= n && a[i] == a[i+2]) {            l = i; r = i + 2; break;        }    } printf("%d %d\n", l, r);    return 0;}