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#include <stdio.h> #include <stdbool.h> #include <string.h> // 题目给出的数组 int arr[100] = { 5,6,8,6,9,1,6,1,2,4,9,1,9,8,2,3,6,4,7,7,5,9,5,0,3,8,7,5,8,1,5,8,6,1, 8,3,0,3,7,9,2, 7,0,5,8,8,5,7,0,9,9,1,9,4,4,6,8,6,3,3,8,5,1,6,3,4,6,7,0,7,8,2,7,6,8, 9,5,6,5,6,1,4,0,1, 0,0,9,4,8,0,9,1,2,8,5,0,2,5,3,3 }; // 判断date_str是否是arr的子序列 bool is_subsequence(const char *date_str) { int i = 0; // 数组下标 int j = 0; // 字符串下标 int len = strlen(date_str); while (i < 100 && j < len) { if (arr[i] == (date_str[j] - '0')) { j++; } i++; } return j == len; } int main() { // 2023年各月天数 int days_in_month[] = {31,28,31,30,31,30,31,31,30,31,30,31}; int count = 0; char date_str[9]; // "2023mmdd\0" for (int month = 1; month <= 12; month++) { for (int day = 1; day <= days_in_month[month-1]; day++) { // 格式化为 2023mmdd sprintf(date_str, "2023%02d%02d", month, day); if (is_subsequence(date_str)) { count++; } } } printf("符合条件的不同日期数量：%d\n", count); return 0; }
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#include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { int month_day[]={31,28,31,30,31,30,31,31,30,31,30,31}; int total_days=1; int cnt=0; for(int month=0;month<12;month++) { total_days+=month_day[month]; } for(int year=1901;year<=2000;year++) { if(year%400==0||(year%4==0&&year%100!=0)) month_day[1]=29; for(int month=0;month<12;month++) { int weekday=total_days%7; if(weekday==0) cnt++; total_days+=month_day[month]; } } printf("%d",cnt); return 0; }
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#include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { int month_day[]={31,28,31,30,31,30,31,31,30,31,30,31}; int total_day=6; int cnt=0; for(int month=0;month<12;month++) { for(int day=1;day<=month_day[month];day++) { int weekday=total_day%7; if(day==1||day==11||day==21||day==31||weekday==6||weekday==0) cnt++; total_day++; } } printf("%d",cnt); return 0; }
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#include <stdio.h> #include <stdlib.h> #include <string.h> int month_day[]={31,28,31,30,31,30,31,31,30,31,30,31}; int num[]={13,1,2,3,5,4,4,2,2,2}; int sum(const char *data) { int a[10]; int total=0; for(int i=0;i<8;i++) { a[i]=data[i]-'0'; total+=num[a[i]]; } return total; } int main(int argc, char *argv[]) { int cnt=0; char data[10]; for(int year=2000;year<=2024;year++) { if(year%400==0||(year%4==0&&year%100!=0)) month_day[1]=29; else month_day[1]=28; for(int month=1;month<=12;month++) { int max=month_day[month-1]; if(year==2024&&month==4) max=13; for(int day=1;day<=max;day++) { sprintf(data,"%04d%02d%02d",year,month,day); int total=sum(data); if(total>50) cnt++; } if(year==2024&&month==4) break; } } printf("%d",cnt); return 0; }
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#include <stdio.h> #include <stdlib.h> #include <string.h> int check(int num) { while(num>0) { if(num%10==1) return 1; num/=10; } return 0; } int main(int argc, char *argv[]) { int month_day[]={0,31,28,31,30,31,30,31,31,30,31,30,31}; int sum=0; int weekday=0; for(int month=1;month<=12;month++) { for(int day=1;day<=month_day[month];day++) { int x=check(month); int y=check(day); int z=(weekday==1); if(x||y||z) sum+=5; else sum+=1; weekday=(weekday+1)%7; } } printf("%d",sum); return 0; }
