AtCoder Regular Contest 059

C - いっしょ / Be Together

枚举即可。

#include<cstdio>
#include<iostream>
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<deque>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
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;
}