junmoyo

#include<stdio.h>

#include<math.h>

int main(void)

{

const double PI = 3.141592653;

//double dDegree = 0.0;

double dRadian = 0.0;

double dResultATan = 0.0;

//dDegree = 45.0f;

double dX = 1.3;

double dY = 1.9;

dRadian = (PI / 180) * 45;

dResultATan = atan2(dY, dX);

printf("X : %g, Y: %g \n", dX, dY);

printf("atan : %f\n", dResultATan);

return 0;

}

/// 아크 탄제트를 구하는 함수.

#include<stdio.h>

#include<math.h>

int main(void)

{ 

 const double PI = 3.141592653; 

 double dDegree = 0.0;

 double dRadian = 0.0; 

 double dResultASin = 0.0; 

 dDegree = 45.0f; 

 dRadian = (PI / 180) * 45;

 dResultASin = asin(dRadian);

 printf("Degree : %f\n", dDegree);

 printf("Radian : %f\n", dRadian); 

 printf("asin : %f\n", dResultASin);

 return 0;

}

#include<stdio.h>

#include<math.h>

int main(void)

{ 

double x;

x = sin(1);

printf("sin(1) : %g\n", x);

system("pause");

return 0;

}

#include<stdio.h>

#include<time.h>

int main(void)

{

time_t now;

struct tm t;

char buff[100];

now = time(NULL);

t = *localtime(&now);

strftime(buff, sizeof(buff), "%Y-%m-%d %I : %M : %S %p", &t);

puts(buff);

system("pause");

return 0;

}

#include<stdio.h>

#include<time.h>

int main(void)

{

time_t now;

struct tm t;

now = time(NULL);

t = *localtime(&now);

puts(asctime(&t));

system("pause");

return 0;

}

#include <stdio.h>

#include<time.h>

void main(void)

{

time_t s1, s2;

double gop;

int i;

time(&s1);

system("pause");

time(&s2);

printf("runnig time : %g (seconds)  \n", difftime(s2, s1));

system("pause");

}

#include<stdio.h>

#include<time.h>

int main(void)

{

time_t now;

struct tm t;

time(&now);

t = *localtime(&now);

t.tm_mday += 100;

mktime(&t);

printf("%s + 100 Days \n", ctime(&now));

printf("%4d . %d . %d . %d : %d : %d \n", t.tm_year, t.tm_mon, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec);

system("pause");

return 0;

}

//

//  main.c

//  128

//

//  Created by 이준모 on 2018. 2. 8..

//  Copyright © 2018년 이준모. All rights reserved.

//

#include <stdio.h>

#include <time.h>

int main(int argc, const char * argv[])

{

    // insert code here...

    time_t now;

    time(&now);

    printf("현재 날짜 및 시간 : %s", ctime(&now));

    return 0;

}

#include <stdio.h>

#include <time.h>

#include <sys/timeb.h>

#include <memory.h>

int main(int argc, const char * argv[])

{

    struct timeb tb; // _timeb use windows 

    struct tm t;

    ftime(&tb); // _ftime use windows

    t= *localtime(&tb.time);

    printf("현재 날짜 및 시간 : %4d. %d. %d. %d. %d. %d. %d \n",t.tm_year+1900, t.tm_mon+1, t.tm_mday, t.tm_hour, t.tm_min, t. tm_sec, tb.millitm);

    return 0;

}

#ifndef _TM_DEFINED

struct tm {

        int tm_sec;     /* seconds after the minute - [0,59] */

        int tm_min;     /* minutes after the hour - [0,59] */

        int tm_hour;    /* hours since midnight - [0,23] */

        int tm_mday;    /* day of the month - [1,31] */

        int tm_mon;     /* months since January - [0,11] */

        int tm_year;    /* years since 1900 */

        int tm_wday;    /* days since Sunday - [0,6] */

        int tm_yday;    /* days since January 1 - [0,365] */

        int tm_isdst;   /* daylight savings time flag */

        };

#define _TM_DEFINED

#include<stdio.h>

#include<time.h>

int main(void)

{

time_t now;

struct tm t;

time(&now);

t = *localtime(&now);

printf("%d . %d . %d        %d : %d : %d \n", t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec);

system("pause");

return 0;

}