import extensions; public program() { var s := "abcd"; console.printLine(s," starts with ab: ",s.startingWith("ab")); console.printLine(s," starts with cd: ",s.startingWith("cd")); console.printLine(s," ends with ab: ",s.endingWith("ab")); console.printLine(s," ends with cd: ",s.endingWith("cd")); console.printLine(s," contains ab: ",s.containing("ab")); console.printLine(s," contains bc: ",s.containing("bc")); console.printLine(s," contains cd: ",s.containing("cd")); console.printLine(s," contains az: ",s.containing("az")); console.printLine(s," index of az: ",s.indexOf(0, "az")); console.printLine(s," index of cd: ",s.indexOf(0, "cd")); console.printLine(s," index of bc: ",s.indexOf(0, "bc")); console.printLine(s," index of ab: ",s.indexOf(0, "ab")); console.readChar() }