#include <stdio.h> #include <time.h> int main() { struct tm start = {0}; start.tm_year = 2025 - 1900; start.tm_mon = 0; // January start.tm_mday = 1; struct tm end = start; end.tm_mon = 2; // March double seconds = difftime(mktime(&end), mktime(&start)); printf("%.0f days", seconds / (60 * 60 * 24)); return 0; }