6 条题解

  • 0
    @ 2025-11-2 9:58:06
    #include<stdio.h>
    int main(){
        int T;
        scanf("%d",&T);
        while(T--){
            int N;
            long long a=0;
            scanf("%d",&N);
            for(int i=2;i<=N;i++){
                long long sum=1;
                for(int  j=1;j<=i;j++){
                      sum*=j; 
                }
              if(i%2==0){
                a+=sum;
            }else{
                a-=sum;
            }
            }
            printf("%lld\n",a+1);
        }
    }
    
    • 0
      @ 2025-10-28 17:09:30
      #include<stdio.h>
      long long jiecheng(long long a){
      	if(a==1)return 1;
      	return a*jiecheng(a-1);
      }//基础的递归
      int main(){
      	int t;
      	scanf("%d",&t);
      	while(t--){
      		int n;
      		scanf("%d",&n);
      		long long ans = 0;
      		for(int i = 1;i <= n;i++){
      			int x = i;
      			if(x&1 && x!=1){
      			ans -= jiecheng(i);
      			}else{
      				ans += jiecheng(i);
      			}
      		}
      		printf("%lld\n",ans);
      	}
      }
      
      • 0
        @ 2025-7-7 10:59:19

        //计算1!+2!-3!+4!-5!+……N!

        #include <stdio.h> #include <math.h>

        int main() { int n; int a = 1; int b = 0; int f = -1; int sum = 0; printf("计算1!+2!-3!+4!-5!+……N!\n"); printf("请输入N的值:"); scanf_s("%d", &n); if (n == 1) { sum = 1; } else { for (int i = 1; i <= n; i++) { for (int j = 1; j <= i; j++) { a = a * j; } sum = sum + (a * f); f = -f; a = 1; } // 计算-1!+2!-3!+4!-5!+……N!的值 sum = sum + 2; //由于原题的第一项为正值,需要加2 } printf("结果为:%d", sum); return 0; }

        • 0
          @ 2024-12-9 0:49:22

          #include<stdio.h>

          int main() { int t; scanf("%d", &t); while (t--) { int n; scanf("%d", &n); if (n == 1) { printf("1\n"); } else { long long sum = 1; for (int a = 2; a <= n; a++) { long long ans = 1; if (a % 2 == 0) { for (int b = 1; b <= a; b++) { ans *= b; } sum += ans; } else { for (int b = 1; b <= a; b++) { ans *= (-b); } sum += ans; }

          } printf("%lld\n", sum); }

          } return 0;

          }

          • 0
            @ 2024-10-21 8:49:58

            #include <stdio.h>

            int main()

            {

            int n;

            scanf("%d",&n);

            while(n--){

            int a;

            scanf("%d",&a);

            if(a==1){

            printf("%d\n",a);

            }else if(a==2){

            printf("%d\n",a+1);

            }else if(a>2){

            int ax=-1;

            long long int sum=2,sam=3,ma=2;

            for(int i=3;i<=a;i++){

            if(i%2!=0){

            ma=i*ma;

            sum=ma*ax+sam;

            sam=sum;

            ax=1;

            }else{

            ma=i*ma;

            sum=ma*ax+sam;

            sam=sum;

            ax=-1;

            }

            }

            printf("%lld\n",sum);

            }

            }

            return 0;

            }

            • 0
              @ 2023-10-19 20:39:13

              #include<stdio.h> int main(){ int t,n; scanf("%d",&t); for(int i=0;i<t;i++){ scanf("%d",&n); long long sum=1,sb=2; for(int j=1;j<=n;j++){ sum=jsum(-1); sb=sb+sum; } printf("%lld\n",sb); } return 0; }

              • 1

              信息

              ID
              180
              时间
              3000ms
              内存
              128MiB
              难度
              6
              标签
              (无)
              递交数
              780
              已通过
              217
              上传者