4 files changed, 154 insertions, 9 deletions
diff --git a/chapter25/docs/examples/BubbleSort.smp b/chapter25/docs/examples/BubbleSort.smp
index 1a4359ae..7327e461 100644
--- a/chapter25/docs/examples/BubbleSort.smp
+++ b/chapter25/docs/examples/BubbleSort.smp
@@ -6,14 +6,12 @@
 // Bubble sort, with reading (parsing) and writing (formatting) the data.
 
 val sort = { sys.aryi64 nums ->
-    var done = false;
-    while( !done ) {
-        done = true;
+    var more = nums;
+    while( more ) {
+        more = null;
         for( var i = 0; i < nums.len-1; i++ )
-            if( nums.buf[i] > nums.buf[i+1] ) {
-                nums.swap(i,i+1);
-                done = false;
-            }
+            if( nums.buf[i] > nums.buf[i+1] )
+                more = nums.swap(i,i+1);
     }
 };
 
@@ -33,7 +31,7 @@ val main = { u8[~][] args ->
     // Bubble sort array of integers
     sort(nums);
 
-    // Print the comma-separated result without the input brackets.
-    nums.csv().write(1);
+    // Print the same bracketed array-list format accepted as input.
+    nums.str().add('\n').write(1);
     return 0;
 };
diff --git a/chapter25/docs/examples/Capitalize.smp b/chapter25/docs/examples/Capitalize.smp
new file mode 100644
index 00000000..72b5df70
--- /dev/null
+++ b/chapter25/docs/examples/Capitalize.smp
@@ -0,0 +1,23 @@
+// -*- mode: java;  -*-
+
+// An implementation of
+// https://sampleprograms.io/projects/capitalize/
+
+val main = { u8[~][] args ->
+    if( args# > 2 ) {
+        sys.io.p("Use quotes around multiple strings.\n");
+        return 0;
+    }
+    if( args# != 2 || args[1]# == 0 ) {
+        sys.io.p("Usage: please provide a string\n");
+        return 0;
+    }
+
+    u8[~] input = args[1];
+    var output = new u8[input# + 1];
+    sys.ary.copy(output,0,input,0,input#);
+    output[0] = sys.char.toupper(input[0]);
+    output[input#] = '\n';
+    sys.io.p(output);
+    return 0;
+};
diff --git a/chapter25/docs/examples/Dijkstra.smp b/chapter25/docs/examples/Dijkstra.smp
new file mode 100644
index 00000000..57e1fad4
--- /dev/null
+++ b/chapter25/docs/examples/Dijkstra.smp
@@ -0,0 +1,73 @@
+// -*- mode: java;  -*-
+
+// An implementation of
+// https://sampleprograms.io/projects/dijkstra/
+
+val shortestPath = { sys.aryi64 matrix, int nodes, int src, int dst ->
+    i64 infinity = (1 << 63)-1;
+    var dist = new i64[nodes];
+    var visited = new sys.adt.bitset();
+    // All nodes are infinitely far from each other
+    for( int i=0; i<nodes; i++ ) dist[i] = infinity;
+    // Starting point is zero far from starting point
+    dist[src] = 0;
+
+    i64 result = -1;
+    int count = 0;
+    while( count < nodes && result < 0 ) {
+        int nearest = -1;
+        i64 best = infinity;
+        for( int node=0; node<nodes; node++ )
+            if( !visited.get(node) && dist[node] < best ) {
+                nearest = node;
+                best = dist[node];
+            }
+        if( nearest < 0 ) count = nodes;
+        else {
+            if( nearest == dst ) return best;
+            visited.set(nearest);
+            for( int node=0; node<nodes; node++ ) {
+                i64 weight = matrix.get(nearest*nodes + node);
+                if( weight > 0 && !visited.get(node) && best+weight < dist[node] )
+                    dist[node] = best+weight;
+            }
+        }
+        count++;
+    }
+    return result;
+};
+
+val usage = { ->
+    sys.io.p("Usage: please provide three inputs: a serialized matrix, a source node and a destination node\n");
+    return 0;
+};
+
+val main = { u8[~][] args ->
+    // Exactly 3 args
+    if( args# != 4 ) return usage();
+    // First is a serialized square matrix of positive numbers
+    var matrix = sys.aryi64.parseAryI64(args[1]);
+    if( !matrix ) return usage();
+    if( !matrix.len ) return usage();
+    // All numbers are positive
+    for( int i=0; i<matrix.len; i++ )
+        if( matrix.get(i) < 0 ) return usage();
+    // Matrix is square
+    int nodes = 0;
+    while( nodes*nodes < matrix.len ) nodes++;
+    if( nodes*nodes != matrix.len )
+        return usage();         // Not a square matrix
+
+    // src,dst are values within the matrix
+    i64 src = sys.aryu8.atoi(args[2]);
+    i64 dst = sys.aryu8.atoi(args[3]);
+    if( src < 0 || src >= nodes || dst < 0 || dst >= nodes )
+        return usage();         // Source and destination land within the graph
+
+     i64 cost = shortestPath(matrix,nodes,src,dst);
+     if( cost >= 0 ) {
+         new sys.aryu8().num(cost).add('\n').write(1);
+         return 0;
+     }
+    return usage();
+};
diff --git a/chapter25/docs/examples/FileIO.smp b/chapter25/docs/examples/FileIO.smp
new file mode 100644
index 00000000..29f037bd
--- /dev/null
+++ b/chapter25/docs/examples/FileIO.smp
@@ -0,0 +1,51 @@
+// -*- mode: java;  -*-
+
+// An implementation of
+// https://sampleprograms.io/projects/file-input-output/
+
+val FILE = "output.txt";
+
+val main = { u8[~][] args ->
+    var str = new sys.aryu8();
+    str.addAry("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.\n");
+    str.addAry("Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.\n");
+    str.addAry("Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.\n");
+    str.addAry("Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.\n");
+
+    // Create
+    i32 fd = sys.io.create(FILE);
+    if( fd == -1 ) return _error();
+    // Write
+    int wrote = sys.io.writeOff(fd,str.buf,0,str.len);
+    if( wrote == -1 ) return _error();
+    if( wrote != str.len ) return _error2(-2);
+    // Close
+    if( sys.io.close(fd) != 0 ) return _error();
+
+    // Open
+    i32 fd2 = sys.io.open(FILE);
+    if( fd2 == -1 ) return _error();
+    // Read
+    var got = sys.io.read(fd2);
+    if( got# != str.len ) return _error2(-3);
+    // Close
+    if( sys.io.close(fd2) != 0 ) return _error();
+
+    // Check contents are equal
+    if( sys.ary.cmp(got,0,str.buf,0,str.len) )
+        return _error2(-4);
+
+    // Remove
+    if( sys.io.remove(FILE) != 0 ) return _error();
+
+    sys.io.p("File I/O succeeded\n");
+    return 0;
+};
+
+val _error2 = { i32 errno ->
+    sys.io.remove(FILE);
+    new sys.aryu8().addAry("Failed with error code ").num(errno).add('\n').write(sys.libc.STDERR);
+    sys.libc._exit(errno);
+};
+
+val _error = { -> _error2(sys.libc.errno); };