https://www.nowcoder.com/acm/contest/173#question T1:https://www.nowcoder.com/acm/contest/173/A 题意概述:对于一个序列,求把序列中的每一个数删去后的新方差*长度的平方. 良心T1,送分送温暖,把方差的式子化开,O(n)就可以解决. # include <cstdio> # include <iostream> # define R register int using namespace…
T1 化一下试子就ok code #include<cstdio> #include<algorithm> inline long long read() { long long x = 0,f = 1; char c = getchar(); while(c < '0' || c > '9') {if(c == '-')f = -1; c = getchar(); } while(c <= '9' && c >= '0') x = x *…