using namespace std;
string a;
long long sum=0;
int main(){
	cin>>a;
	int n=a.size();
	for(int i=0;i<n;i++){
		if((a[i]-'0')%5==0){
			sum+=i+1;
		}else if(i>0&&((a[i-1]-'0')*10+a[i]-'0')%4==0){
			if((a[i]-'0')%4==0){
				sum++;
			}
			sum+=i;
		}else if((a[i]-'0')%4==0){
			sum++;
		}
	}
	cout<<sum;
	return 0;
}

只需用sort排序，再注意判断即可

code

#include <bits/stdc++.h> using namespace std; int n; struct s{ int m; int e; int c; int p; }a[100050]; bool cmp(s x,s y){ if(x.c+x.e+x.m+x.p!=y.c+y.e+y.m+y.p){ return x.c+x.e+x.m+x.p>y.c+y.e+y.m+y.p; } else if(x.m!=y.m){ return x.m>y.m; } else if(x.c!=y.c){ return x.c>y.c; } else if(x.e!=y.e){ return x.e>y.e; } } int main(){ cin>>n; for(int i=1;i<=n;i++){ cin>>a[i].m>>a[i].e>>a[i].c>>a[i].p; } sort(a+1,a+n+1,cmp); for(int i=1;i<=n;i++){ cout<<a[i].m<<" "<<a[i].e<<" "<<a[i].c<<" "<<a[i].p<<endl; } return 0; }