7-1 求矩阵的局部极大值

#include<stdio.h>
int main()
{
	int m, n, i, j;
	int arr[100][100];
	scanf("%d %d", &m, &n);
	for (i = 1; i <= m; i++)
	{
		for (j = 1; j <= n; j++)
		{
			scanf("%d", &arr[i][j]);
		}
	}
	int flag = 0;
	for (i = 2; i <= m-1; i++)
	{
		for (j = 2; j <= n-1; j++)
		{
			if (arr[i][j] > arr[i - 1][j] && arr[i][j] > arr[i + 1][j] && arr[i][j] > arr[i][j - 1] && arr[i][j] > arr[i][j + 1])
			{
				printf("%d %d %d\n", arr[i][j], i, j);
				flag = 1;
			}
		}
	}
	if (flag == 0)
	{
		printf("None %d %d", m, n);
	}
	return 0;
}

7-2 求矩阵各行元素之和

#include<stdio.h>
int main()
{
	int m, n, i, j;
	int arr[10][10];
	scanf("%d %d", &m, &n);
	for (i = 0; i < m; i++)
	{
		for (j = 0; j < n; j++)
		{
			scanf("%d", &arr[i][j]);
		}
	}
	int sum = 0;
	for (i = 0; i < m; i++)
	{
		for (j = 1; j < n; j++)
		{
			arr[1][0] += arr[i][j];
		}
	}
	for (i = 0; i < m; i++)
		printf("%d\n", arr[i][0]);
	return 0;
}

7-3 判断上三角矩阵

#include<stdio.h>
int main()
{
	int T, i, j, n,k;
	int a[10][10];
	scanf("%d", &T);
	for (k = 0; k < T; k++)
	{
		scanf("%d", &n);
		for (i = 0; i < n; i++)
		{
			for (j = 0; j < n; j++)
			{
				scanf("%d", &a[i][j]);
			}
		}

		int flag = 1;
		for (int x = 1; x < n; x++)
		{
			for (int y = 0; y < x; y++)
			{
				if (a[x][y] != 0)
				{
					flag = 0;
					break;
				}
					
			}
			if (flag == 0)
				break;
		}
		if (flag == 1)
			printf("YES\n");
		else
			printf("NO\n");
	}
	return 0;
}

7-4 点赞

#include<stdio.h>
int main()
{
	int n, m, i, j;
	int num = 0, max = 0, maxpos = 1000;
	scanf("%d", &n);
	int flag[1001] = { 0 };
	for (i = 0; i < n; i++)
	{
		scanf("%d", &m);
		for (j = 0; j < m; j++)
		{
			scanf("%d", &num);
			flag[num]++;
		}
	}
	for (i = 1000; i > 0; i--)
	{
		if (flag[i] > max)
		{
			max = flag[i];
			maxpos = i;
		}
	}
	printf("%d %d", maxpos, max);

	return 0;
}