lab programs

Author: Shahid6174

NQueens.c

@@ -0,0 +1,67 @@
+#include<stdio.h>
+#include<stdlib.h>
+#include<math.h>
+
+int a[30], count = 0;
+
+// Function prototypes
+int place(int pos);
+void print_sol(int n);
+void queen(int n);
+
+// Function to check if a queen can be placed in a particular position
+int place(int pos) {
+    int i;
+    for (i = 1; i < pos; i++) {
+        if ((a[i] == a[pos]) || (abs(a[i] - a[pos]) == abs(i - pos)))
+            return 0;
+    }
+    return 1;
+}
+
+// Function to print the board configuration for a solution
+void print_sol(int n) {
+    int i, j;
+    count++;
+    printf("\n\nSolution #%d:\n", count);
+    for (i = 1; i <= n; i++) {
+        for (j = 1; j <= n; j++) {
+            if (a[i] == j)
+                printf("Q\t");
+            else
+                printf("*\t");
+        }
+        printf("\n");
+    }
+}
+
+// Function to find all solutions to the N-Queens problem
+void queen(int n) {
+    int k = 1;
+    a[k] = 0;
+    while (k != 0) {
+        do {
+            a[k]++;
+        } while ((a[k] <= n) && !place(k));
+        
+        if (a[k] <= n) {
+            if (k == n)
+                print_sol(n);
+            else {
+                k++;
+                a[k] = 0;
+            }
+        }
+        else
+            k--;
+    }
+}
+
+int main() {
+    int n;
+    printf("Enter the number of Queens\n");
+    scanf("%d", &n);
+    queen(n);
+    printf("\nTotal solutions = %d\n", count);
+    return 0;
+}

NQueens.exe

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+#include <stdio.h>
+
+// Function prototypes
+void printSubset(int subset[], int size);
+void findSubsets(int set[], int n, int target);
+
+// Function to print the current subset
+void printSubset(int subset[], int size) {
+    printf("{ ");
+    for (int i = 0; i < size; i++) {
+        printf("%d ", subset[i]);
+    }
+    printf("}\n");
+}
+
+// Function to find subsets that sum to the given target
+void findSubsets(int set[], int n, int target) {
+    int subset[n];
+    int totalSubsets = 1 << n; // Total number of subsets (2^n)
+
+    // Iterate over all possible subsets
+    for (int i = 0; i < totalSubsets; i++) {
+        int sum = 0;
+        int subsetSize = 0;
+
+        // Check which elements are included in the current subset
+        for (int j = 0; j < n; j++) {
+            if (i & (1 << j)) {
+                subset[subsetSize++] = set[j];
+                sum += set[j];
+            }
+        }
+
+        // If the sum of the current subset is equal to the target, print the subset
+        if (sum == target) {
+             printSubset(subset, subsetSize);
+        }
+    }
+}
+
+int main() {
+    int set[10], n, target;
+
+    // Input number of elements in the set
+    printf("Enter the number of elements in the set: ");
+    scanf("%d", &n);
+
+    // Input elements of the set
+    printf("Enter the elements of the set: ");
+    for (int i = 0; i < n; i++) {
+        scanf("%d", &set[i]);
+    }
+
+    // Input the target sum
+    printf("Enter the target sum: ");
+    scanf("%d", &target);
+
+    // Find and print subsets that sum to the target
+    findSubsets(set, n, target);
+
+    return 0;
+}