add problem 48 and test function

Author: supercoderhawk

C/1-50/48-Rotate-Image.c

@@ -0,0 +1,57 @@
+/*
+ * You are given an n x n 2D matrix representing an image.
+
+ * Rotate the image by 90 degrees (clockwise).
+
+ * Follow up:
+ * Could you do this in-place?
+ * Created by supercoderx on 2017/8/14.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+
+void rotate(int **matrix, int matrixRowSize, int matrixColSize) {
+    int tmp;
+    for (int i = 0; i < matrixRowSize / 2; i++) {
+        if (2 * i == matrixRowSize - 1)
+            break;
+        for (int j = i; j < matrixRowSize - i - 1; j++) {
+            // 上<->右
+            tmp = matrix[i][j];
+            matrix[i][j] = matrix[j][matrixRowSize - 1 - i];
+            matrix[j][matrixRowSize - 1 - i] = tmp;
+            // 下<->左
+            tmp = matrix[matrixRowSize - 1 - j][i];
+            matrix[matrixRowSize - 1 - j][i] = matrix[matrixRowSize - 1 - i][matrixColSize - 1 - j];
+            matrix[matrixRowSize - 1 - i][matrixColSize - 1 - j] = tmp;
+            // 上<->下
+            tmp = matrix[i][j];
+            matrix[i][j] = matrix[matrixColSize - 1 - i][matrixRowSize - 1 - j];
+            matrix[matrixColSize - 1 - i][matrixRowSize - 1 - j] = tmp;
+        }
+    }
+}
+
+void testRotate() {
+    int count = 3, **matrix = malloc(sizeof(int *) * count);
+    matrix[0] = malloc(sizeof(int) * count);
+    matrix[1] = malloc(sizeof(int) * count);
+    matrix[2] = malloc(sizeof(int) * count);
+    //matrix[3] = malloc(sizeof(int)*count);
+    //matrix[4] = malloc(sizeof(int)*count);
+
+    for (int k = 0; k < count; ++k) {
+        for (int i = 0; i < count; ++i) {
+            matrix[k][i] = k * count + i + 1;
+        }
+    }
+    rotate(matrix, count, count);
+    for (int i = 0; i < count; i++) {
+        for (int j = 0; j < count; ++j) {
+            printf("%d,", matrix[i][j]);
+        }
+        printf("\n");
+    }
+
+
+}