C语言计算日期差的方法示例

#include <bits/stdc++.h>using namespace std;int to_day(int y, int m, int d){  int mon[] = {0,31,28,31,30,31,30,31,31,30,31,30,31};  int day = 0;  int i;  for(i=1; i<y; i++){    day += (i%4==0 && i%100!=0 || i%400==0)? 366 : 365;  }  if(y%4==0 && y%100!=0 || y%400==0) mon[2]++;  for(i=1; i<m; i++){      day += mon[i];  }  return day + d;}int diff(int y1, int m1, int d1, int y2, int m2, int d2){  int a = to_day(y1, m1, d1);  int b = to_day(y2, m2, d2);  return b-a;}int main({  //int n = diff(1864,12,31,1865,1,1);  int n = diff(1864,12,31,2012,3,18);  printf("%d/n", n);  return 0;}int n = diff(1864,12,31,2012,3,18);// 输出 53768