ACM ICPC Team
思路:遍历
难度:Easy

#include<stdio.h>
int max_topics=0;
int result[500];
int main()
{
    int T,N;
    char ACM_Team[500][500];
    scanf("%d%d",&T,&N);

    for (int i = 0; i < T; i++)
    {
        getchar();
        for (int j = 0; j < N; j++)
        {
            scanf("%c", &ACM_Team[i][j]);
        }

    }
    for (int i = 0; i < T-1; i++)
    for (int j = i+1; j < T; j++)
    {
        int topics = 0;
        if (j == i)
            continue;
        for (int k = 0; k < N; k++)
        {
            if (ACM_Team[i][k] == '1' || ACM_Team[j][k] == '1')
                topics++;
        }
        if (topics>max_topics)
            max_topics = topics;
        result[topics]++;
    }
    printf("%d\n%d\n", max_topics, result[max_topics]);

    return 0;
}

TaumB
思路:简单的比较,取小值就可(有极端数据,C的整形范围太小要溢出,int64 oj上编译过不了,double不会溢出了,但是丢失精度,纠结。。。最后只能找了段Python的代码)
难度:Easy

#!/usr/bin/py
if __name__ == '__main__':
t = input()
for _ in xrange(t):
b, w = map(int, raw_input().split())
x, y, z = map(int, raw_input().split())

print min(b*x, b*(y+z)) + min(w*(x+z), w*y)

Sherlock and Squares
思路:求解两个方根之间有几个整数,注意边界的判断
难度:Easy

#include<stdio.h>
#include<math.h>
int Number[100];
int Full_Sqrt(int A, int B)
{
    int a = ceil(sqrt((float)A));
    int b = floor(sqrt((float)B));
    if (a > b)
        return 0;
    else
    {
            return b - a+1;
    }
}
int main()
{
    int T, A, B;
    scanf("%d",&T);
    for (int i = 0; i < T; i++)
    {
        scanf("%d%d",&A,&B);
        Number[i] = Full_Sqrt(A,B);
    }
    for (int i = 0; i < T; i++)
    {
        printf("%d\n",Number[i]);
    }
    return 0;
}

Sherlock and GCD
思路:找数组有无一个最大公约数,且数组里有1的时候可直接确认为YES
难度:Easy

#include<stdio.h>
int arr[100];
int result[10];
int Mod(int a, int b)
{
    int c=a%b;
    while (c != 0)
    {
        a = b;
        b = c;
        c = a%b;
    }
    return b;
}
int GCD(int N)
{
    if (N < 2)
        return 0;
    int temp=Mod(arr[0], arr[1]);
    if (temp == 1)
        return 1;
    for (int i = 2; i < N; i++)
    {
        temp = Mod(arr[i], temp);
        if (temp == 1)
            return 1;
    }
    return 0;
}
int main()
{
    int T, N;
    scanf("%d",&T);
    for (int i = 0; i < T; i++)
    {
        scanf("%d", &N);
        for (int j=0; j < N; j++)
        {
            scanf("%d", &arr[j]);
        }
        result[i] = GCD(N);
    }
    for (int i = 0; i < T; i++)
    if (result[i] == 1)
        printf("YES\n");
    else
        printf("NO\n");
    return 0;
}

Sherlock and The Beast
思路:寻找数据是否满足此公式N=5x+3y 找到x和y后按照相应的位数输出一个最大整数值
难度:Easy

#include<stdio.h>
int result[20][2];
void Decent(int n, int i)
{
    int temp = n;
    if (n < 3)
        result[i][0] = -1;
    else
    {
        while (temp>0)
        {
            if (temp % 3 == 0)
                break;
            else
                temp -= 5;
        }
        result[i][0] = temp;
        result[i][1] = n - temp;
    }
}
int main()
{
    int T, Dec[20];
    scanf("%d",&T);
    for (int i = 0; i < T; i++)
    {
        scanf("%d",&Dec[i]);
        Decent(Dec[i],i);
    }
    for (int i = 0; i < T; i++)
    {
        if (result[i][0] < 0)
            printf("-1\n");
        else
        {
            for (int j = 0; j < result[i][0]; j++)
            {
                printf("5");
            }
            for (int k = 0; k < result[i][1]; k++)
            {
                printf("3");
            }
            printf("\n");
        }
    }
    return 0;
}

Filling Jars
思路:又是纸老虎,记录个总数据再除以N就行(int会溢出,用long)
难度;Easy

#include<stdio.h>
int main()
{
    long N, M;
    long a, b, k, sum = 0;
    scanf("%ld%ld",&N,&M);
    for (int i = 0; i < M; i++)
    {
        scanf("%ld%ld%ld",&a,&b,&k);
        sum += (b - a + 1)*k;
    }
    printf("%ld\n",sum/N);
    return 0;
}

Max Min
思路:查找数组内部方差最小的子集(子集大小需要输入),并输出子集的最大最小值的差。这题有数据,为了方便查找,需要提前排序,一般的排序会超时,这里使用C自带的快排。
难度:Moderate

#include<stdio.h>
#include<stdlib.h>
int comp(const void*a, const void*b)
{
    return *(int*)a - *(int*)b;
}
int main()
{
    int N,K,Unfairness=99999999,temp;
    int a[100000];
    scanf("%d%d",&N,&K);
    for (int i = 0; i < N; i++)
        scanf("%d",&a[i]);
    qsort(a, N, sizeof(int),comp);

    for (int i = 0; i < N-K; i++)
    {
        temp = a[i+K-1]-a[i];
        if (Unfairness> temp)
            Unfairness = temp;
    }
    printf("%d\n",Unfairness);
    return 0;
}

Song of Pi
思路:思路真的没什么好说的,但是遇到个怪事:最初的代码的OJ测试结果和自己跑出来的不一样。。。可能是回车键缓存或者变量的不同?也或许是编译器的缘故?或者是C默认的字符串分割函数的问题?最后改成这样就过了
难度:Easy

#include<stdio.h>
#include<string.h>
int result[100];
int main()
{
    int T, i , j ;
    int Pi[29] = { 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3, 2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3, 3 };
    char Song[500];
    char YES[30] = "It's a pi song.", NO[30] = "It's not a pi song.";
    scanf("%d", &T);
    getchar();
    for (i = 0; i < T; i++)
    {
        int k = 0,time = 0;
        gets(Song);
        for (int j = 0; j < strlen(Song); j++)
        {
            if (j == strlen(Song) - 1)
            {
                if (Pi[time] != (j - k+1))
                {
                    result[i] = -1;
                    break;
                }
            }

            if (Song[j] == ' ')
            {
                if (Pi[time] != (j - k) )
                {
                    result[i] = -1;
                    break;
                }
                time++;
                k = j+1;
            }
        }
    }
    for (i = 0; i < T; i++)
    {
        if (result[i]==0)
            puts(YES);
        else
            puts(NO);
    }
    return 0;
}

Identify Smith Numbers
思路:两个点:质因数的分解和位数分解(分解出整数的个十百千位等等),其中质因数分解采用Pollard Rho因数分解法(主要原理是从小到大每次挑一个数出来,看是否能与原数整除,这个方法很快也很简单,推荐使用),位数分解比较简单不作说明,注意输入的边界,如果是1,直接返回就行。
难度:Easy

#include<stdio.h>
int Digit_Sum(int n)
{
    int sum = 0;
    while (n != 0)
    {
        sum += n % 10;
        n /= 10;
    }
    return sum;
}
int main()
{
    int n,i,j=0,sum,sum2=0;
    int DIVISOR[100];
    scanf("%d",&n);
    if (n == 1)
    {
        printf("0\n");
        return 0;
    }
    sum = Digit_Sum(n);

    for (i = 2; i < n; i++)
    {
        while (n!=i)
        if (n%i == 0){
            DIVISOR[j++] = i;
            n = n / i;
        }
        else
            break;
    }
    DIVISOR[j++] = n;
    for (i = 0; i < j; i++)
        sum2 += Digit_Sum(DIVISOR[i]);
    if (sum == sum2)
        printf("1\n");
    else
        printf("0\n");
    return 0;
}

The Time in Words
思路:我觉的这道题难度标错了,太简单了
难度:Moderate

int main()
{
    int hour,minute;
    scanf("%d",&hour);
    scanf("%d", &minute);
    if (minute == 0)
        printf("%s o' clock\n",word[hour]);
    else
    {
        if (minute < 30)
        {
            if (minute == 15)
                printf("quarter past %s", word[hour]);
            else
                printf("%s minutes past %s", word[minute], word[hour]);
        }
        else if (minute == 30)
            printf("half past %s", word[hour]);
        else
        {
            if (minute == 45)
                printf("quarter to %s", word[hour+1]);
            else
                printf("%s minutes to %s", word[60-minute], word[hour+1]);
        }
    }
    return 0;
}

Modified Kaprekar Numbers
思路:换C++了,C语言对抗溢出我已经玩够了(貌似OJ不认识C的int64),还有注意没有结果要输出,INVALID RANGE,我就是这里没看见,下了数据才看见
难度:Easy

#include<iostream>
using namespace std;
int judge(long long i, long long length)
{
    long long L, R, digit = length / 2, temp = (i*i);
    if ((digit * 2) != length)
        digit++;

    for (long long i = 0; i < digit; i++)
        temp /= 10;
    L = temp;
    for (long long i = 0; i < digit; i++)
        temp *= 10;
    R = (i*i) - temp;
    if ((L + R) == i)
        return i;
    else
        return -1;
}
int main()
{
    long long p, q, j = 0, result[100000];
    long long length=1,judge_length=10,temp;
    cin >> p >> q;
    while ((p*p) >= judge_length)
    {
        judge_length *= 10;
        length++;
    }
    for (long long i = p; i <= q; i++)
    {
        if ((i*i) >= judge_length){
            length++;
            judge_length *= 10;
        }
        temp = judge(i, length);
        if (temp != -1)
        {
            result[j] = temp;
            j++;
        }
    }
    if (j == 0)
    {
        printf("INVALID RANGE");
        return 0;
    }
    for (long long i = 0; i < j; i++)
        printf("%d ", result[i]);
    return 0;
}

Is Fibo
思路:一个循环和一个二分查找即可(PS:我差点记不住二分查找了)
难度:Easy

#include<iostream>
#include<string>
using namespace std;
string a = "IsFibo";
string b = "IsNotFibo";
int result[1000];
long long array[1000];
int IsFbi(long long N, int Right)
{
    long long Left = 0;
    long long Mid;
    while (Left<=Right)
    {
        Mid = (Left + Right) / 2;
        if (N == array[Mid])
            return 1;
        else if (N < array[Mid])
            Right = Mid-1;
        else
            Left = Mid+1;
    }
    return 0;
}
int main()
{
    long long  fi,i=3,temp=1;
    long long  T, N;
    array[1] = 1,array[2] = 1;
    while (array[i - 1] <= 10000000000)
    {
        array[i] = array[i - 1] + array[i - 2];
        i++;
    }
    cin >> T;
    for (int k = 0; k < T; k++)
    {
        cin >> N;
        if (IsFbi(N,i))
            result[k] = 1;
    }
    for (int j = 0; j < T; j++)
    {
        if (result[j] == 1)
            cout << a << endl;
        else
            cout << b << endl;
    }
    return 0;
}