C語言學習_test1

1.從鍵盤上輸入5個數，輸出最大的、最小的元素以及他們的下标

#include<stdio.h>

int main(void)

{

int i, j, k, max, min;

int a[10] = {0};

printf("input number:");

for(i = 0; i < 5; i++)

scanf("%d", &a[i]);

max = min = a[0];

j = k = 0;

if(max < a[i])

max = a[i];

j = i;

}

else if(min > a[i])

min = a[i];

k = i;

printf("%d %d %d %d\n", j, max, k, min);

return 0;

2.從鍵盤上輸入16個整數，儲存在4*4的二維數組中輸出偶數行和偶數列的元素。

#include <stdio.h>

int a[5][5] = {0};

int i, j;

printf("input numbers:");

for(i = 0; i < 4; i++)

for(j = 0; j < 4; j++)

scanf("%d", &a[i][j]);

if(i % 2 == 0 && j % 2 == 0)

printf("%d\n", a[i][j]);

3.在有序數組中，輸入一個數，若這個很數存在，則輸出數及其位置，若不存在，則輸出資訊。

#define M 10

int a[M] = {-1,6,8,10,15,20,21,25,29,55};

int n;//查找的數

int low, high, mid;

int found;

low = 0;

high = M - 1;

found = 0;

printf("input n:");

scanf("%d", &n);

while(low <= high)

mid = (low + high) / 2;

if(n == a[mid])

found = 1;

break;

else if(n < a[mid])

high = mid - 1;

else

low = mid + 1;

if(found == 1)

printf("index of %d is %d", n, mid);

printf("there is not %d", n);