算法笔记

算法笔记
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1001 害死人不偿命的(3n+1)猜想

#include<stdio.h>

int main(){
   int n, count = 0;
   scanf("%d", &n);
   while(n != 1){
      if(n % 2 == 0) n = n / 2;
      else n = (3 * n + 1) / 2;
      count++;
   }
   printf("%d", count);
   return 0;
}

1032 挖掘机技术哪家强

#include<stdio.h>
const int maxn = 1e5;
int school[maxn] = {0};

int main(){
   int n, schoolid, score;
   int k = 1, max = -1;
   scanf("%d", &n);
   if(n > maxn) return 0;
   for(int i = 0; i < n; i++){
      scanf("%d %d", &schoolid, &score);
      school[schoolid] += score;
   }
   for(int i = 1; i <= n; i++){
      if(school[i] > max){
         max = school[i];
         k = i;
      }
   }
   printf("%d %d\n", k, max);
   return 0;
}

1036 跟奥巴马一起编程

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

int main(){
   int n, row;
   char c;
   scanf("%d %c", &n, &c);
   if(n < 3 || n > 20) return 0;
   row = round(n / double(2));
   for(int i = 0; i < row; i++){
      for(int j = 0; j < n; j++){
         if(i == 0 || i == row-1){
            if(j ==n-1) printf("%c\n", c);
            else printf("%c", c);
         }
         else {
            if(j == 0) printf("%c", c);
            else if(j == n-1) printf("%c\n", c);
            else printf("%c", ' ');
         }
      }
   }
   return 0;
}

1022 D进制的A+B

#include<stdio.h>

int main(){
   int a, b, d, i = 0, num[40];
   scanf("%d %d %d", &a, &b, &d);
   int sum = a + b;
   do{
      num[i++] = sum % d;
      sum = sum / d;
   }while(sum != 0);
   for(int j = i-1; j >= 0; j--){
      printf("%d", num[j]);
   }
   return 0;
}

1009 说反话

#include<stdio.h>
#include<string.h>

int main(){
   char str[90], ans[90][90];
   gets(str);
   int len = strlen(str), row = 0, col = 0;
   for(int i = 0; i < len; i++){
      if(str[i] != ' ') ans[row][col++] = str[i];
      else{
         ans[row][col] = '\0';   //字符数组末尾必须添加结束符'\0'，数字数组不需要
         row++;
         col = 0;    //行+1，列恢复至0
      } 
   }
   for(int j = row; j >= 0; j--){
      printf("%s", ans[j]);
      if(j > 0) printf(" ");
   }
   return 0;
}

#include<cstdio>

int main(){
   int word = 0;
   char ans[90][90];
   while(scanf("%s", ans[word]) != EOF){
      word++;
   }
   for(int j = word-1; j >= 0; j--){
      printf("%s", ans[j]);
      if(j > 0) printf(" ");
   }
   return 0;
}

1006 换个格式输出整数

#include<cstdio>

int main(){
   int a, n = 0;
   char ans[30];
   scanf("%d", &a);
   if(a <= 0 || a >= 1000) return 0;
   for(int i =0; i < a/100; i++) ans[n++] = 'B';
   for(int j =0; j < a%100/10; j++) ans[n++] = 'S';
   for(int k =1; k <= a%10; k++) ans[n++] = k+'0';    //int转化为char，char(67)是转化成ascii码对应字符
   puts(ans);
   return 0;
}

#include <stdio.h>
int main()
{
    int n,i,h,t,u;
    scanf("%d",&n);
    h = n / 100;//百位
    t = (n % 100) / 10;//十位
    u = n % 10;//个位
    for(i = 0; i < h; i++){
        printf("B");
    }
    for(i = 0; i < t; i++){
        printf("S");
    }
    for(i = 0; i < u; i++){
        printf("%d",i+1);
    }
    printf("\n");
    return 0;
}