FOJ Accepted Source

foj_1016.cpp

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

int main() 
{ 
    double x,y,a,b;
	double m,n;
	freopen("data.txt", "r", stdin);
	while(scanf("%lf %lf %lf %lf", &a, &b, &x, &y) !=EOF)
	{
		if(a==0 && b==0 && x==0 && y==0)
			return 1;
		if(a<b)
		{
			double t = a;
			a = b;
			b = t;
		}
		if(x<y)
		{
			double t = x;
			x = y;
			y = t;
		}

		if(a>x && b>y)
		{
			printf("Escape is possible.\n");
			continue;
		}

		else if(x*x+y*y>a*a+b*b)
		{
			printf("Box cannot be dropped.\n");
			continue;
		}
		else
		{
			m = (a - sqrt((double)(x*x+y*y-b*b)))/2;
			n = (b - sqrt((double)(x*x+y*y-a*a)))/2;
			if(m*m+n*n>y*y)
				printf("Escape is possible.\n");
			else
				printf("Box cannot be dropped.\n");
		}

	}

	return 0;

	fclose(stdin);
}

foj_1405.cpp

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

int main()
{
	long a, b;
	char str[30];
	freopen("data.txt", "r", stdin);
	while(scanf("%ld %ld", &a, &b) != EOF)
	{
		memset(str, 0, 30);
		long res = a-b;
		sprintf(str, "%ld", res);
		int len = strlen(str);
		int q = len%3;
		for(int i=0; i<len; i++)
		{
			printf("%c", str[i]);
			int n;
				n = i+1;
			int start;
			if(res >= 0)
				start = 1;
			else
				start = 2;
			if(n%3 == q && n<len-2 && n >= start)
			{
				printf(",");
			}
		}
		printf("\n");

	}
	fclose(stdin);
}

foj_1475.cpp

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


bool compare(char *s1, char *s2)
{
	int n = strlen(s1);
	if(n != strlen(s2))
	{
		return false;
	}
	else
	{
		for(int i=0; i<n; i++)
		{
			char c1 = s1[i];
			char c2 = s2[i];

			if(c1>='A' && c1<='Z')
			{
				c1 += 32;
			}
			if(c2>='A' && c2<='Z')
			{
				c2 += 32;
			}
			if(c1 != c2)
				return false;
		}
	}
	return true;
}

int main()
{
	char word[1000][20];
	int n;
	int flag[1000];
	for(int i=0; i<1000; i++)
	{
		memset(word[i], 0 ,20);
	}
	freopen("data.txt", "r", stdin);
	while(scanf("%d", &n) != EOF)
	{
		getchar();

		for(int i=0; i<n; i++)
		{
			gets(word[i]);
		}

		for(int i=0; i<n; i++)
		{
			flag[i] = 1;
		}


		for(int i=0; i<n; i++)
			for(int j=i+1; j<n; j++)
			{
				if(!flag[j] || !flag[i])
					continue;
				if(compare(word[i], word[j]))
				{
					flag[j] = 0;
				}
			}
		int sum = 0;
		for(int i=0; i<n; i++)
		{
			if(flag[i])
				sum++;
		}

		printf("%d\n", sum);
		for(int i=0; i<n; i++)
		{
			memset(word[i], 0 ,20);
		}

	}
	fclose(stdin);
}

foj_1715.cpp

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

int func(int m, int i)
{
	if(i == 0)
		return 1;
	else if(i == 1)
		return m;
	else if(i > m/2)
	{
		return func(m, m-i);
	}
	else
	{
		int sum1 = 1;
		int sum2 = 1;
		for(int j = 0; j<i; j++)
		{
			sum1 *= m-j;
			sum2 *= i-j;
		}
		return sum1/sum2;
	}
}

int main() 
{ 
    int m,n;

	freopen("data.txt", "r", stdin);
	while(scanf("%d %d", &n, &m) !=EOF)
	{
		int sum = 0;
		for(int i=0; i<m; i++)
		{
			int tmp1 = func(m, i);
			int tmp2 = 1;
			for(int j=0; j<n; j++)
			{
				tmp2 *= m-i;
			}
			if(i%2 == 0)
			{
				sum +=(tmp1*tmp2);
			}
			else
			{
				sum -=(tmp1*tmp2);
			}

		}
		printf("%d\n", sum);
	}

	fclose(stdin);
}