洛谷oj题单【入门2】分支结构-入门难度（Java）

来源：https://www.luogu.com.cn/training/101#problems

P5709 【深基2.习6】Apples Prologue / 苹果和虫子

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int m = sc.nextInt(); int t = sc.nextInt(); int s = sc.nextInt(); if (t == 0) System.out.println(0); else { int apple = (int) Math.ceil(s / t); if (m <= apple) System.out.println(0); else if(s % t != 0) System.out.println(m - apple - 1); else System.out.println(m - apple); } } }

P5710 【深基3.例2】数的性质

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int x = sc.nextInt(); //两种都符合 System.out.print(((x % 2 == 0) && ((x > 4) && (x <= 12))) ? 1 : 0); System.out.printf(" "); //至少符合一种 System.out.print(((x % 2 == 0) || ((x > 4) && (x <= 12))) ? 1 : 0); System.out.printf(" "); //只符合一种 System.out.print(((x % 2 == 0) ^ ((x > 4) && (x <= 12))) ? 1 : 0); System.out.printf(" "); //都不符合 System.out.print(((x % 2 != 0) && ((x <= 4) || (x > 12))) ? 1 : 0); } }

P5711 【深基3.例3】闰年判断

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); if(n % 4 == 0 && n % 100 != 0 || n % 400 == 0) System.out.println(1); else System.out.println(0); } }

P5712[【深基3.例4】Apples

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); if(n == 0 || n == 1) System.out.println("Today, I ate "+n+" apple."); else System.out.println("Today, I ate "+n+" apples."); } }

P5713 【深基3.例5】洛谷团队系统

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); if(11 + 3 * n > 5 * n) System.out.println("Local"); else System.out.println("Luogu"); } }

P5714 【深基3.例7】肥胖问题

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); double m = sc.nextDouble(); double h = sc.nextDouble(); double BMI = m / (h * h); if (BMI < 18.5) System.out.println("Underweight"); else if (BMI >= 18.5 && BMI < 24) System.out.println("Normal"); else { if (BMI - (int) BMI == 0) System.out.printf("%2.0f\n", BMI);//用题目中给的m=120/h=1.4计算出整数部分不会超过两位           ，所以占位符取2 else if (BMI * 10 - (int) (BMI * 10) == 0) System.out.printf("%3.1f\n", BMI);//2位整数+1位小数点
  
 
  
 
  
 
  
 
  
 
 ，所以占位符取3










，保留小数点后1位 
  
  
  
  
  ，以下类推 else if (BMI * 100 - (int) (BMI * 100) == 0) System.out.printf("%4.2f\n", BMI); else if (BMI * 1000 - (int) (BMI * 10000) == 0) System.out.printf("%5.3f\n", BMI); else System.out.printf("%6.4f\n", BMI); //用题目中给的m=120/h=1.4计算出整数部分不会超过两位 //所以6位有效数字最多就是2位整数+4位小数 System.out.println("Overweight"); } } }

P5715 【深基3.例8】三位数排序

import java.util.Arrays; import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int[] str = new int[3]; for (int i = 0; i < 3; i++) { str[i] = sc.nextInt(); } int a = str[0], b = str[1], c = str[2]; Arrays.sort(str); for (int i=0;i<3;i++) { System.out.print(str[i]+" "); } } }

P5716 [【深基3.例9】月份天数

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int[] str = {0,31,28,31,30,31,30,31,31,30,31,30,31};//常规年份天数 int y = sc.nextInt();//年 int m = sc.nextInt();//月 if(y % 4 == 0 && y % 100 != 0 || y % 400 == 0 )//判断是否为闰年
  
  
  
  
  
 ，方便对2月进行判断 str[2] = 29; System.out.printf("%d",str[m]);//方便输出 } }

P1085 [NOIP2004 普及组] 不高兴的津津

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int a,b; int max = 0,res = 0;//分别为最大值
 


 


 


 


 


，最终结果 for (int i = 0; i < 7; i++) { a = sc.nextInt(); b = sc.nextInt(); if(a + b > 8 && a + b > max){ max = a + b; res = i + 1;//i以0开头 
 
 
 
 
 ，所以应加1 } } System.out.println(res); } }

P1909 [NOIP2016 普及组] 买铅笔

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); //数量 //三组数据 int a1 = sc.nextInt(); int a2 = sc.nextInt(); int b1 = sc.nextInt(); int b2 = sc.nextInt(); int c1 = sc.nextInt(); int c2 = sc.nextInt(); //计算钱数 int a = (int) (Math.ceil((double)n/(double)a1) * a2); //第一组 int b = (int) (Math.ceil((double)n/(double)b1) * b2); //第二组 int c = (int) (Math.ceil((double)n/(double)c1) * c2); //第三组 //比较 int min = a<b?a:b; min = min<c?min:c; //输出 System.out.println(min); } }

P1422 小玉家的电费

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); double sum = 0; if(n < 150){ sum = n * 0.4463; }else if(n >= 150 && n < 400){ sum = 150 * 0.4463 + (n -150) * 0.4663; } else if (n >= 401) { sum = 150 * 0.4463 + 250 * 0.4663 + (n - 400) * 0.5663; } System.out.printf("%.1f",sum); } }

P1424 小鱼的航程(改进版)

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int x = sc.nextInt();//从周x算起 int n = sc.nextInt();//天数 int sum = 0; for (int i = 0; i < n; i++) { //在循环中进行星期的判断 switch (x){ case 1:case 2:case 3:case 4:case 5:sum += 250;//工作日接着游泳 case 6:x++;continue;//周六休息 case 7:x = 1;continue;//周日重置为周一
   
   
   
   
   
 ，并且休息不游泳 } x++;//进入下一天 } System.out.println(sum); } }

P1888 三角函数

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int c = sc.nextInt(); int min = 0,max = 0; //求最小边 min = a < b ? a : b; min = min < c ? min :c; //求斜边 max = a > b ? a : b; max = max > c ? max :c; //辗转相除法求最大公因子 int n = 0; for (int i = 1; i < min; i++) { if(max % i == 0 && min % i ==0){ n = i; } } System.out.println(min/n+"/"+max/n ); } }

P1046 [NOIP2005 普及组] 陶陶摘苹果

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int[] arr = new int[10]; for (int i = 0; i < arr.length; i++) { arr[i] = sc.nextInt(); } int n = sc.nextInt();//总高度 int num = 0;//个数 for (int i = 0; i < arr.length; i++) { if(n+30 >= arr[i]) num++; } System.out.println(num); } }

P4414 [COCI2006-2007#2] ABC

import java.util.Scanner; import java.util.Arrays; public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); int[] a = new int[3]; a[0] = in.nextInt(); a[1] = in.nextInt(); a[2] = in.nextInt(); Arrays.sort(a);//排序 String str = in.next(); char ch1 = str.charAt(0);//第一个字母 char ch2 = str.charAt(1);//第二个字母 char ch3 = str.charAt(2);//第三个字母 System.out.println(a[ch1 - A] + " " + a[ch2 - A] + " " + a[ch3 - A]); } }